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can do things like map memory pages, intercept calls and interrupts, and preempt the real-mode program, allowing real-mode programs to be multitasked like protected-mode programs. By intercepting the hardware and software I/O of the real-mode program and tracking the state that the V86 program expects, it can allow multiple programs to share the same hardware without interfering with each other. So V86 mode provides a way for real-mode programs designed for a single-tasking environment (like DOS) to run concurrently in a multitasking environment.
360:
examines what the real mode program is trying to do and either acts as a proxy to interface with the hardware, emulates the intended function the real-mode program was trying to access, or terminates the real-mode program if it is trying to do something that cannot either be allowed or be adequately supported (such as reboot the machine, set a video display into a mode that is not supported by the hardware and is not emulated, or write over operating system code).
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528:; their more recent formal name is Virtual-8086 Mode Extensions, abbreviated VME (older documentation may use "Virtual 8086 mode enhancements" as the VME acronym expansion). Some later Intel 486 chips also support it. The enhancements address mainly the 8086 virtualization overhead, with a particular focus on (virtual) interrupts. Before the extensions were publicly documented in the P6 documentation, the official documentation referred to the famed
25:
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intent is that the VMM run the guest in paged-real mode at CPL0, and with page faults intercepted. The VMM is responsible for setting up a shadow page table that maps guest physical memory to the appropriate system physical addresses. The behavior of running a guest in paged real mode without intercepting page faults to the VMM is undefined.
543:. Because the VME interrupt speed-up enhancements were found useful for non-VM86 protected tasks, they can also be enabled separately by setting only bit number 1 (0x2 in value), which is called PVI (Protected Mode Virtual Interrupts). Detecting whether a processor supports VME (including PVI) is done using the
649:
For example, if one program writes to a display, then another program gets control and writes to the same display, and then the first program gets control back, it will try to use the display as if the second program had not changed it. The V86 monitor can intercept the display writes, keep track of
1092:
To facilitate virtualization of real mode, the VMRUN instruction may legally load a guest CR0 value with PE = 0 but PG = 1. Likewise, the RSM instruction is permitted to return to paged real mode. This processor mode behaves in every way like real mode, with the exception that paging is applied. The
615:
can do virtual 8086 mode in guests, too, but it can also just run the guest in "paged real mode" using the following steps: you create a SVM (Secure
Virtual Machine) mode guest with CR0.PE=0, but CR0.PG=1 (that is, with protected mode disabled but paging enabled), which is ordinarily impossible, but
359:
0 and in protected mode. Only the 8086 program runs in VM86 mode and at privilege level 3. When the real-mode program attempts to do things like access certain I/O ports to use hardware devices or access certain regions in its memory space, the CPU traps these events and calls the V86 monitor, which
363:
The V86 monitor can also deny permission gently by emulating the failure of a requested operation—for example, it can make a disk drive always appear not ready when in fact it has not even checked the drive but simply will not permit the real-mode program to access it. Also, the V86 monitor
565:
In virtual 8086 mode, the basic idea is that when IOPL is less than 3, PUSHF/POPF/STI/CLI/INT/IRET instructions will treat the value of VIF in the real 32-bit EFLAGS register as the value of IF in the simulated 16-bit FLAGS register (32-bit PUSHFD/POPFD continues to GP fault). VIP will cause a GP
515:
When interrupts (hardware, software and int instruction) occur, the processor switches off the VM86 mode and returns to work in full protected mode to handle the interrupt. Also, before servicing the interrupt, the DS, ES, FS, and GS registers are pushed on the new stack and zeroed.
650:
the display state for each program, and switch the real display between them according to which program the user has selected to interact with presently. The V86 monitor emulates independent displays for each program using only one real display.
354:
To use virtual 8086 mode, an operating system sets up a virtual 8086 mode monitor, which is a program that manages the real-mode program and emulates or filters access to system hardware and software resources. The monitor must run at
598:
brings back the ability to run virtual 8086 mode from x86-64 long mode, but it has to be done by transitioning the (physical) processor to VMX root mode and launching a logical (virtual) processor itself running in virtual 8086 mode.
1055:"Intel added unrestricted guest mode on Westmere micro-architecture and later Intel CPUs, it uses EPT to translate guest physical address access to host physical address. With this mode, VMEnter without enable paging is allowed."
547:
instruction, with an initial EAX value of 0x1, by testing the value of second bit (bit number 1, 0x2 in value) in EDX register, which is set if VME is supported by the processor. In Linux, this latter bit is reported as the
330:
scheme identical to that of real mode (for compatibility reasons), which creates 20-bit linear addresses in the same manner as 20-bit physical addresses are created in real mode, but are subject to protected mode's memory
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1002:
a VM entry is allowed only to guests with paging enabled that are in protected mode or in virtual-8086 mode. Guest execution in other processor operating modes need to be specially handled by the VMM
833:
1017:. Also beware that this sample code is more complicated than strictly booting the logical processor in virtual 8086 mode; its ultimate goal is make some real-mode BIOS calls.
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524:
The
Pentium architecture added a number of enhancements to the virtual 8086 mode. These were however documented by Intel only starting with the subsequent
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and later Intel processors usually can start the virtual processor directly in real mode using the "unrestricted guest" feature (which itself requires
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fault on the setting of simulated IF, directing the OS to process any pending interrupts. PVI is the same idea but only affects CLI/STI instructions.
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how to do this from Linux (not that the code is pretty dated, so might not work as-is with current kernels) more up-to-date code can be found
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Gnomes, Lee; "Behind The Scenes: The Making of the 386", Intel
Corporation, Special 32-Bit Issue Solutions, November/December 1985, page 19
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is mentioned because it was especially the extensive library of existing DOS programs that Intel had in mind when they designed V86 mode.
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technique that allowed multiple 8086 processors to be emulated by the 386 chip. It emerged from the painful experiences with the
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CPUs have been found to feature a broken VME implementation. The second generation Ryzen (2000 series) has fixed this issue.
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Windows NT-based operating systems also use VM86 mode, but with very limited direct hardware access. Some boot loaders (e.g.
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Intel 64 and IA-32 Architectures
Software Developer's Manual, Volume 2 (2A, 2B, 2C & 2D): Instruction Set Reference, A-Z
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Intel 64 and IA-32 Architectures
Software Developer's Manual, Volume 3 (3A, 3B, 3C & 3D): System Programming Guide
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609:); this method removes the need to resort to the nested virtual 8086 mode simply to run the legacy BIOS for booting.
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1066:"If the “unrestricted guest” VM-execution control is 1, the “enable EPT” VM-execution control must also be 1"
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Intel 64 and IA-32 Architectures
Software Developer's Manual, Volume 3B: System Programming Guide, Part 2
958:
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347:. Consequently, the processor can switch between VM86 and non-VM86 tasks, enabling multitasking legacy (
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532:, which was omitted from the public documentation and shared only with selected partners under
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developed the
Virtual Mode bit at the register set, paving the way to this environment.
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854:"Mailing List Archive: Re: 2.6.14: CR4 not needed to be inspected on the 486 anymore?"
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319:, which by itself was not suitable to run concurrent real-mode applications well.
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programs which use protected mode execute using user mode under the emulator.)
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mechanism is still active, and it is transparent to the real mode code; thus,
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while the processor is running a protected mode operating system. It is a
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mechanism is reconfigured to work just like under real mode, but the
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AMD64 Architecture
Programmer's Manual, Volume 2: System Programming
488:
The most common problem by running 8086 code from protected mode is
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is still applicable, and so is the isolation of the address space.
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CS 686: Special Topic: Intel EM64T and VT Extensions (Spring 2007)
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Activating VME is done by setting bit number 0 (0x1 in value) of
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is allowed for SVM guests if the host intercepts page faults.
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2008:
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959:"Revision Guide for AMD Family 17h Models 00h-0Fh Processors"
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612:
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449:
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469:
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2732:
List of Intel graphics processing units (2013 or earlier)
1950:
1902:
1689:
1364:
659:
465:
457:
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348:
133:
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1043:
A list of Intel processors that support VT-x but not EPT
2955:
Memory management as a function of an operating system
519:
483:
49:. Unsourced material may be challenged and removed.
993:. September 2009. p. 29-1. Archived from
899:"Virtual Mode Extensions on the Pentium Processor"
878:"Pentium Protected Mode Virtual Interrupts (PVI)"
3349:
2862:Intel International Science and Engineering Fair
2572:Intel Corporation Inc. v CPM United Kingdom Ltd
500:. As mentioned, by working under VM86 mode the
1756:
938:
809:Pentium Pro and Pentium II System Architecture
2928:
1385:
1116:
801:
799:
797:
795:
793:
257:
241:First supported platform shown in parentheses
3274:International Symposium on Memory Management
2562:Intel Corp. v. Advanced Micro Devices, Inc.
2552:Advanced Micro Devices, Inc. v. Intel Corp.
2935:
2921:
1392:
1378:
1230:Advanced Programmable Interrupt Controller
1123:
1109:
805:
790:
264:
250:
2842:List of mergers and acquisitions by Intel
928:. May 2020. pp. 3–199, 3–221, 3–222.
812:. Addison-Wesley. pp. 427, 465–480.
718:"Windows NT 4.0 Workstation Architecture"
576:
109:Learn how and when to remove this message
2832:List of semiconductor fabrication plants
2557:High-Tech Employee Antitrust Litigation
2470:Process–architecture–optimization model
872:
870:
684:"Sending software to do hardware's job"
3350:
1028:"Intel Virtualization Technology List"
581:Virtual 8086 mode is not available in
343:The virtual 8086 mode is a mode for a
2942:
2916:
1373:
1275:Intel Display Power Saving Technology
1104:
736:
681:
1399:
867:
47:adding citations to reliable sources
18:
3373:Programming language implementation
2983:Input–output memory management unit
2577:Silvaco Data Systems v. Intel Corp.
1330:Performance acceleration technology
1090:. November 2021. pp. 515–516.
492:which is totally different between
13:
2817:Intel Outstanding Researcher Award
2677:Mac transition to Intel processors
2672:Intel Foundation Achievement Award
520:Virtual-8086 mode extensions (VME)
16:Feature of specific microprocessor
14:
3384:
2887:Supervisor Mode Access Prevention
2837:List of Intel manufacturing sites
562:file, under the "flags" section.
3332:
3331:
3322:
3321:
3312:
3311:
3302:
3301:
3292:
3291:
2485:Intel HD, UHD, and Iris Graphics
774:"Virtual 8086 Mode - OSDev Wiki"
484:Memory addressing and interrupts
23:
3154:Concurrent mark sweep collector
2867:Regeneron Science Talent Search
2717:Dynamic video memory technology
1573:P6 variant (Enhanced Pentium M)
1070:
1059:
1048:
1030:. Ark.intel.com. Archived from
1020:
974:
951:
939:Michal Necasek (May 12, 2017).
932:
912:
891:
846:
682:Yager, Tom (November 5, 2004).
34:needs additional citations for
3279:Region-based memory management
1240:Client Initiated Remote Access
1198:4Group Holdings (50% owned by
826:
766:
730:
710:
701:
675:
653:
643:
372:It is used to execute certain
1:
2727:List of Intel microprocessors
1350:Stable Image Platform Program
842:. May 2020. p. 2-17.
669:
3327:Memory management algorithms
3139:Automatic Reference Counting
2977:Translation lookaside buffer
1295:Intel system development kit
7:
3317:Automatic memory management
3116:C dynamic memory allocation
2812:Intel Mobile Communications
2737:I/O Acceleration Technology
1280:Intel Modular Server System
1235:Cache Acceleration Software
619:
402:Windows for Workgroups 3.1x
338:
10:
3389:
3337:Memory management software
3184:Tracing garbage collection
3017:Virtual memory compression
2877:Single-chip Cloud Computer
1250:Flexible Display Interface
299:) allows the execution of
3287:
3261:
3235:
3202:
3129:
3101:
3058:
3025:
2992:
2963:
2950:
2882:Software Guard Extensions
2872:Simple Firmware Interface
2664:
2613:
2592:
2585:
2544:
2457:
2397:
2209:
2007:
1949:
1900:
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1543:
1534:
1407:
1207:
1193:
1138:
1130:
1077:"15.19 Paged Real Mode".
941:"VME Broken on AMD Ryzen"
3111:Static memory allocation
3103:Manual memory management
636:
416:(since 1995) running in
367:
3169:Garbage-first collector
3144:Boehm garbage collector
3050:x86 memory segmentation
2682:Intel Architecture Labs
739:"Grub2 Booting Process"
313:hardware virtualization
3174:Mark–compact algorithm
2971:Memory management unit
1568:P6 variant (Pentium M)
1285:Intel Quick Sync Video
1245:Direct Media Interface
1088:Advanced Micro Devices
856:. Gossamer-threads.com
754:Cite journal requires
577:64-bit and VMX support
526:P6 (microarchitecture)
480:in Virtual 8086 mode.
303:applications that are
194:System Management Mode
2747:IM Flash Technologies
2742:IA-32 Execution Layer
2722:Intel Extreme Masters
2712:Intel Developer Forum
2567:Intel Corp. v. Hamidi
1300:Intel Upgrade Service
631:x86 assembly language
3121:new and delete (C++)
2822:Intel SHA extensions
1000:on January 5, 2010.
607:Extended Page Tables
478:BIOS interrupt calls
438:virtual DOS machines
317:80286 protected mode
305:incapable of running
43:improve this article
3358:X86 operating modes
3027:Memory segmentation
2802:Intel Compute Stick
2797:Intel Cluster Ready
2702:Convera Corporation
806:T. Shanley (1998).
345:protected-mode task
124:Part of a series on
58:"Virtual 8086 mode"
3269:Automatic variable
3253:Unreachable memory
3179:Reference counting
3149:Cheney's algorithm
3131:Garbage collection
2857:Intel PRO/Wireless
2367:Sandy Bridge-based
1536:Microarchitectures
1521:Microarchitectures
1220:Accounts & SSO
1180:Wind River Systems
476:, and execute the
408:2.x (since 1992),
382:Concurrent DOS 386
214:x86 virtualization
3345:
3344:
3297:Memory management
3045:Virtual 8086 mode
2944:Memory management
2910:
2909:
2902:Timeline of Intel
2772:The Beauty Inside
2660:
2659:
2540:
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2453:
2452:
1826:
1825:
1745:
1744:
1355:Virtual 8086 mode
1270:Intel Clear Video
1170:Recon Instruments
819:978-0-201-30973-7
569:First generation
510:memory protection
490:memory addressing
418:386 Enhanced Mode
326:VM86 mode uses a
289:virtual real mode
285:virtual 8086 mode
274:
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184:Virtual 8086 mode
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3222:Dangling pointer
3217:Buffer over-read
3189:Strong reference
3060:Memory allocator
2937:
2930:
2923:
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2897:Intel Tera-Scale
2779:The Power Inside
2590:
2589:
2372:Ivy Bridge-based
1963:8/16-bit databus
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1750:Current products
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386:Windows/386 2.10
351:) applications.
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156:emulation mode (
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2465:Tick–tock model
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2382:Broadwell-based
2273:Extreme Edition
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2003:
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715:
711:
706:
702:
692:
690:
680:
676:
672:
667:
666:
658:
654:
648:
644:
639:
622:
579:
556:
549:
522:
486:
370:
357:privilege level
341:
270:
218:Intel Pentium 4
115:
104:
98:
95:
52:
50:
40:
28:
17:
12:
11:
5:
3386:
3376:
3375:
3370:
3368:Intel products
3365:
3363:Virtualization
3360:
3343:
3342:
3340:
3339:
3329:
3319:
3309:
3307:Virtual memory
3299:
3288:
3285:
3284:
3282:
3281:
3276:
3271:
3265:
3263:
3259:
3258:
3256:
3255:
3250:
3245:
3239:
3237:
3233:
3232:
3230:
3229:
3227:Stack overflow
3224:
3219:
3214:
3208:
3206:
3200:
3199:
3197:
3196:
3194:Weak reference
3191:
3186:
3181:
3176:
3171:
3166:
3161:
3156:
3151:
3146:
3141:
3135:
3133:
3127:
3126:
3124:
3123:
3118:
3113:
3107:
3105:
3099:
3098:
3096:
3095:
3090:
3085:
3080:
3075:
3070:
3064:
3062:
3056:
3055:
3053:
3052:
3047:
3042:
3037:
3035:Protected mode
3031:
3029:
3023:
3022:
3020:
3019:
3014:
3009:
3004:
2998:
2996:
2994:Virtual memory
2990:
2989:
2987:
2986:
2980:
2974:
2967:
2965:
2961:
2960:
2958:
2957:
2951:
2948:
2947:
2940:
2939:
2932:
2925:
2917:
2908:
2907:
2905:
2904:
2899:
2894:
2889:
2884:
2879:
2874:
2869:
2864:
2859:
2854:
2849:
2844:
2839:
2834:
2829:
2824:
2819:
2814:
2809:
2804:
2799:
2794:
2789:
2784:
2783:
2782:
2775:
2768:
2756:
2753:The Innovators
2749:
2744:
2739:
2734:
2729:
2724:
2719:
2714:
2709:
2704:
2699:
2694:
2689:
2684:
2679:
2674:
2668:
2666:
2662:
2661:
2658:
2657:
2655:
2654:
2649:
2644:
2642:Brian Krzanich
2639:
2634:
2629:
2624:
2621:
2617:
2615:
2611:
2610:
2608:
2607:
2602:
2596:
2594:
2587:
2583:
2582:
2580:
2579:
2574:
2569:
2564:
2559:
2554:
2548:
2546:
2542:
2541:
2538:
2537:
2535:
2534:
2529:
2524:
2519:
2514:
2509:
2504:
2499:
2498:
2497:
2492:
2487:
2482:
2472:
2467:
2461:
2459:
2455:
2454:
2451:
2450:
2448:
2447:
2442:
2437:
2432:
2427:
2422:
2417:
2412:
2407:
2401:
2399:
2395:
2394:
2392:
2391:
2390:
2389:
2384:
2379:
2374:
2369:
2364:
2354:
2353:
2352:
2347:
2342:
2337:
2332:
2327:
2322:
2317:
2312:
2307:
2302:
2297:
2292:
2282:
2281:
2280:
2275:
2270:
2265:
2255:
2254:
2253:
2248:
2238:
2237:
2236:
2231:
2220:
2218:
2207:
2206:
2204:
2203:
2198:
2193:
2192:
2191:
2186:
2184:NetBurst-based
2181:
2171:
2166:
2165:
2164:
2159:
2154:
2149:
2144:
2139:
2134:
2129:
2119:
2118:
2117:
2111:
2100:
2099:
2098:
2093:
2083:
2078:
2077:
2076:
2071:
2066:
2061:
2056:
2051:
2041:
2040:
2039:
2034:
2029:
2018:
2016:
2005:
2004:
2002:
2001:
1996:
1991:
1990:32-bit databus
1988:
1983:
1978:
1973:
1972:16-bit databus
1970:
1964:
1960:
1958:
1947:
1946:
1944:
1943:
1937:
1931:
1925:
1919:
1912:
1910:
1898:
1897:
1895:
1894:
1888:
1882:
1875:
1873:
1865:
1864:
1862:
1861:
1855:
1848:
1846:
1832:
1828:
1827:
1824:
1823:
1821:
1820:
1815:
1814:
1813:
1808:
1803:
1798:
1793:
1783:
1778:
1773:
1767:
1765:
1751:
1747:
1746:
1743:
1742:
1740:
1739:
1738:
1737:
1727:
1726:
1725:
1715:
1714:
1713:
1708:
1697:
1695:
1686:
1685:
1683:
1682:
1677:
1672:
1671:
1670:
1660:
1659:
1658:
1648:
1647:
1646:
1636:
1635:
1634:
1624:
1623:
1622:
1612:
1611:
1610:
1599:
1597:
1586:
1585:
1583:
1582:
1577:
1576:
1575:
1570:
1560:
1554:
1552:
1538:
1532:
1531:
1529:
1528:
1523:
1518:
1517:
1516:
1511:
1506:
1501:
1500:
1499:
1494:
1489:
1484:
1479:
1474:
1464:
1463:
1462:
1457:
1452:
1447:
1442:
1437:
1427:
1422:
1411:
1409:
1405:
1404:
1397:
1396:
1389:
1382:
1374:
1368:
1367:
1362:
1357:
1352:
1347:
1337:
1332:
1327:
1322:
1317:
1312:
1307:
1302:
1297:
1292:
1287:
1282:
1277:
1272:
1267:
1262:
1257:
1252:
1247:
1242:
1237:
1232:
1227:
1225:Amplify Tablet
1222:
1217:
1211:
1209:
1205:
1204:
1197:
1195:
1191:
1190:
1188:
1187:
1182:
1177:
1172:
1167:
1162:
1159:Intel Security
1155:
1150:
1142:
1140:
1136:
1135:
1128:
1127:
1120:
1113:
1105:
1098:
1097:
1069:
1058:
1047:
1019:
973:
950:
931:
911:
901:. Rcollins.org
890:
880:. Rcollins.org
866:
845:
825:
818:
789:
778:wiki.osdev.org
765:
756:|journal=
729:
709:
700:
673:
671:
668:
665:
664:
652:
641:
640:
638:
635:
634:
633:
628:
621:
618:
578:
575:
521:
518:
494:protected mode
485:
482:
474:protected mode
420:as well as in
412:(since 1993),
404:(since 1992),
400:(since 1991),
396:(since 1990),
392:(since 1988),
388:(since 1987),
384:(since 1987),
380:(since 1987),
369:
366:
340:
337:
309:protected mode
281:microprocessor
272:
271:
269:
268:
261:
254:
246:
243:
242:
238:
237:
236:
235:
225:
211:
201:
191:
181:
171:
164:Protected mode
161:
151:
138:
137:
132:modes for the
130:Microprocessor
126:
125:
117:
116:
31:
29:
22:
15:
9:
6:
4:
3:
2:
3385:
3374:
3371:
3369:
3366:
3364:
3361:
3359:
3356:
3355:
3353:
3338:
3330:
3328:
3320:
3318:
3310:
3308:
3300:
3298:
3290:
3289:
3286:
3280:
3277:
3275:
3272:
3270:
3267:
3266:
3264:
3260:
3254:
3251:
3249:
3246:
3244:
3243:Fragmentation
3241:
3240:
3238:
3234:
3228:
3225:
3223:
3220:
3218:
3215:
3213:
3210:
3209:
3207:
3205:
3204:Memory safety
3201:
3195:
3192:
3190:
3187:
3185:
3182:
3180:
3177:
3175:
3172:
3170:
3167:
3165:
3162:
3160:
3157:
3155:
3152:
3150:
3147:
3145:
3142:
3140:
3137:
3136:
3134:
3132:
3128:
3122:
3119:
3117:
3114:
3112:
3109:
3108:
3106:
3104:
3100:
3094:
3091:
3089:
3086:
3084:
3081:
3079:
3076:
3074:
3071:
3069:
3066:
3065:
3063:
3061:
3057:
3051:
3048:
3046:
3043:
3041:
3038:
3036:
3033:
3032:
3030:
3028:
3024:
3018:
3015:
3013:
3010:
3008:
3007:Memory paging
3005:
3003:
3002:Demand paging
3000:
2999:
2997:
2995:
2991:
2984:
2981:
2978:
2975:
2972:
2969:
2968:
2966:
2962:
2956:
2953:
2952:
2949:
2945:
2938:
2933:
2931:
2926:
2924:
2919:
2918:
2915:
2903:
2900:
2898:
2895:
2893:
2890:
2888:
2885:
2883:
2880:
2878:
2875:
2873:
2870:
2868:
2865:
2863:
2860:
2858:
2855:
2853:
2850:
2848:
2845:
2843:
2840:
2838:
2835:
2833:
2830:
2828:
2825:
2823:
2820:
2818:
2815:
2813:
2810:
2808:
2807:Intel Ireland
2805:
2803:
2800:
2798:
2795:
2793:
2792:Intel Capital
2790:
2788:
2785:
2781:
2780:
2776:
2774:
2773:
2769:
2767:
2766:
2762:
2761:
2760:
2757:
2755:
2754:
2750:
2748:
2745:
2743:
2740:
2738:
2735:
2733:
2730:
2728:
2725:
2723:
2720:
2718:
2715:
2713:
2710:
2708:
2707:Copy Exactly!
2705:
2703:
2700:
2698:
2695:
2693:
2690:
2688:
2685:
2683:
2680:
2678:
2675:
2673:
2670:
2669:
2667:
2663:
2653:
2652:Pat Gelsinger
2650:
2648:
2645:
2643:
2640:
2638:
2637:Paul Otellini
2635:
2633:
2632:Craig Barrett
2630:
2628:
2625:
2622:
2619:
2618:
2616:
2612:
2606:
2603:
2601:
2598:
2597:
2595:
2591:
2588:
2584:
2578:
2575:
2573:
2570:
2568:
2565:
2563:
2560:
2558:
2555:
2553:
2550:
2549:
2547:
2543:
2533:
2530:
2528:
2525:
2523:
2520:
2518:
2515:
2513:
2510:
2508:
2505:
2503:
2500:
2496:
2493:
2491:
2488:
2486:
2483:
2481:
2478:
2477:
2476:
2473:
2471:
2468:
2466:
2463:
2462:
2460:
2456:
2446:
2443:
2441:
2438:
2436:
2433:
2431:
2428:
2426:
2423:
2421:
2418:
2416:
2413:
2411:
2408:
2406:
2403:
2402:
2400:
2396:
2388:
2387:Skylake-based
2385:
2383:
2380:
2378:
2377:Haswell-based
2375:
2373:
2370:
2368:
2365:
2363:
2362:Nehalem-based
2360:
2359:
2358:
2355:
2351:
2348:
2346:
2343:
2341:
2338:
2336:
2333:
2331:
2328:
2326:
2323:
2321:
2318:
2316:
2313:
2311:
2308:
2306:
2303:
2301:
2298:
2296:
2293:
2291:
2288:
2287:
2286:
2283:
2279:
2276:
2274:
2271:
2269:
2266:
2264:
2261:
2260:
2259:
2256:
2252:
2249:
2247:
2244:
2243:
2242:
2239:
2235:
2232:
2230:
2227:
2226:
2225:
2222:
2221:
2219:
2216:
2212:
2208:
2202:
2199:
2197:
2194:
2190:
2187:
2185:
2182:
2180:
2177:
2176:
2175:
2172:
2170:
2167:
2163:
2160:
2158:
2155:
2153:
2150:
2148:
2145:
2143:
2140:
2138:
2135:
2133:
2130:
2128:
2127:Original i586
2125:
2124:
2123:
2120:
2115:
2112:
2110:
2107:
2106:
2104:
2101:
2097:
2094:
2092:
2089:
2088:
2087:
2084:
2082:
2079:
2075:
2072:
2070:
2067:
2065:
2062:
2060:
2057:
2055:
2052:
2050:
2047:
2046:
2045:
2042:
2038:
2035:
2033:
2030:
2028:
2025:
2024:
2023:
2020:
2019:
2017:
2014:
2010:
2006:
2000:
1997:
1995:
1992:
1989:
1987:
1984:
1982:
1979:
1977:
1974:
1971:
1968:
1965:
1962:
1961:
1959:
1956:
1952:
1948:
1941:
1938:
1935:
1932:
1929:
1926:
1923:
1920:
1917:
1914:
1913:
1911:
1908:
1904:
1899:
1892:
1889:
1886:
1883:
1880:
1877:
1876:
1874:
1871:
1866:
1859:
1856:
1853:
1850:
1849:
1847:
1844:
1840:
1836:
1833:
1829:
1819:
1816:
1812:
1809:
1807:
1804:
1802:
1799:
1797:
1794:
1792:
1789:
1788:
1787:
1784:
1782:
1779:
1777:
1774:
1772:
1769:
1768:
1766:
1763:
1759:
1755:
1752:
1748:
1736:
1733:
1732:
1731:
1728:
1724:
1723:Goldmont Plus
1721:
1720:
1719:
1716:
1712:
1709:
1707:
1704:
1703:
1702:
1699:
1698:
1696:
1694:
1691:
1687:
1681:
1678:
1676:
1673:
1669:
1666:
1665:
1664:
1661:
1657:
1654:
1653:
1652:
1649:
1645:
1642:
1641:
1640:
1637:
1633:
1630:
1629:
1628:
1625:
1621:
1618:
1617:
1616:
1613:
1609:
1606:
1605:
1604:
1601:
1600:
1598:
1595:
1591:
1587:
1581:
1578:
1574:
1571:
1569:
1566:
1565:
1564:
1561:
1559:
1556:
1555:
1553:
1550:
1546:
1542:
1539:
1537:
1533:
1527:
1524:
1522:
1519:
1515:
1512:
1510:
1507:
1505:
1502:
1498:
1495:
1493:
1490:
1488:
1485:
1483:
1480:
1478:
1475:
1473:
1470:
1469:
1468:
1465:
1461:
1458:
1456:
1453:
1451:
1448:
1446:
1443:
1441:
1438:
1436:
1433:
1432:
1431:
1428:
1426:
1423:
1421:
1418:
1417:
1416:
1413:
1412:
1410:
1406:
1402:
1395:
1390:
1388:
1383:
1381:
1376:
1375:
1372:
1366:
1363:
1361:
1358:
1356:
1353:
1351:
1348:
1345:
1341:
1338:
1336:
1335:Shooting Star
1333:
1331:
1328:
1326:
1323:
1321:
1318:
1316:
1313:
1311:
1308:
1306:
1303:
1301:
1298:
1296:
1293:
1291:
1288:
1286:
1283:
1281:
1278:
1276:
1273:
1271:
1268:
1266:
1263:
1261:
1258:
1256:
1253:
1251:
1248:
1246:
1243:
1241:
1238:
1236:
1233:
1231:
1228:
1226:
1223:
1221:
1218:
1216:
1213:
1212:
1210:
1206:
1201:
1196:
1194:Joint venture
1192:
1186:
1183:
1181:
1178:
1176:
1173:
1171:
1168:
1166:
1163:
1161:
1160:
1156:
1154:
1151:
1149:
1148:
1144:
1143:
1141:
1137:
1133:
1126:
1121:
1119:
1114:
1112:
1107:
1106:
1103:
1094:
1089:
1086:. Rev. 3.38.
1082:
1081:
1073:
1067:
1062:
1056:
1051:
1044:
1034:on 2014-02-10
1033:
1029:
1023:
1016:
1012:
1008:
1003:
996:
992:
985:
984:
977:
969:
968:
960:
954:
946:
942:
935:
927:
923:
922:
915:
900:
894:
879:
873:
871:
855:
849:
841:
837:
836:
829:
821:
815:
811:
810:
802:
800:
798:
796:
794:
779:
775:
769:
761:
748:
740:
733:
725:
724:
719:
713:
704:
689:
685:
678:
674:
661:
656:
646:
642:
632:
629:
627:
624:
623:
617:
614:
610:
608:
604:
600:
597:
593:
591:
587:
584:
574:
572:
567:
563:
560:
554:
546:
542:
537:
535:
531:
527:
517:
513:
511:
507:
503:
499:
495:
491:
481:
479:
475:
471:
467:
463:
459:
455:
451:
447:
443:
439:
435:
431:
427:
423:
419:
415:
411:
407:
403:
399:
398:Multiuser DOS
395:
391:
387:
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32:This article
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2847:Intel Museum
2777:
2770:
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2759:Inside Films
2751:
2697:Classmate PC
2627:Andrew Grove
2623:Gordon Moore
2620:Robert Noyce
2605:Robert Noyce
2600:Gordon Moore
1831:Discontinued
1668:Cypress Cove
1627:Sandy Bridge
1354:
1290:Intel Reader
1157:
1145:
1139:Subsidiaries
1091:
1079:
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1036:. Retrieved
1032:the original
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995:the original
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970:. June 2018.
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502:segmentation
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390:DESQview 386
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307:directly in
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136:architecture
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41:Please help
36:verification
33:
3248:Memory leak
2827:Intel Teach
1680:Golden Cove
1675:Willow Cove
1656:Cannon Lake
1265:Intel AZ210
1255:Hella Zippy
1005:; see also
945:OS/2 Museum
737:Mike Wang.
693:January 27,
590:legacy mode
394:Windows 3.x
335:mechanism.
283:and later,
198:Intel 386SL
188:Intel 80386
178:Intel 80286
174:Unreal mode
168:Intel 80286
158:NEC V20/V30
3352:Categories
3012:Page table
2545:Litigation
2475:Intel GPUs
2189:Core-based
1953:(external
1841:oriented (
1711:Silvermont
1663:Sunny Cove
1632:Ivy Bridge
1415:Processors
1260:Intel 1103
1038:2014-02-20
905:2014-02-20
884:2014-02-20
860:2014-02-20
783:2020-12-10
670:References
596:Intel VT-x
530:Appendix H
472:) use the
422:Windows 95
378:FlexOS 386
148:Intel 8086
69:newspapers
3159:Finalizer
3040:Real mode
2787:Intel ADX
2527:Codenames
2440:StrongARM
2278:Dual-Core
2251:Dual-Core
2162:Dual-Core
2132:OverDrive
2081:A100/A110
2074:OverDrive
1868:pre-x86 (
1735:Gracemont
1644:Broadwell
1325:Omni-Path
1215:3D XPoint
1175:Virtutech
1011:lesson 24
723:Microsoft
688:InfoWorld
586:long mode
571:AMD Ryzen
498:real mode
456:. (Other
448:, and in
301:real mode
204:Long mode
144:Real mode
3093:ptmalloc
3088:mimalloc
3078:jemalloc
3068:dlmalloc
2964:Hardware
2687:ASCI Red
2647:Bob Swan
2593:Founders
2532:Larrabee
2410:iAPX 432
2345:11th gen
2340:10th gen
2179:P6-based
2069:RapidCAD
1811:14th gen
1806:13th gen
1801:12th gen
1796:11th gen
1791:10th gen
1718:Goldmont
1706:Saltwell
1620:Westmere
1580:NetBurst
1526:Chipsets
1305:Intel740
1208:Products
1165:Mobileye
620:See also
603:Westmere
452:through
444:through
442:SCO UNIX
436:through
339:Overview
293:V86-mode
3164:Garbage
3083:libumem
2985:(IOMMU)
2665:Related
2522:Stratix
2458:Related
2420:Itanium
2335:9th gen
2330:8th gen
2325:7th gen
2320:6th gen
2315:5th gen
2310:4th gen
2305:3rd gen
2300:2nd gen
2295:1st gen
2258:Pentium
2241:Celeron
2201:Tolapai
2122:Pentium
2105:(1998)
2103:Celeron
1994:80387DX
1986:80387SX
1781:Pentium
1776:Celeron
1730:Tremont
1701:Bonnell
1651:Skylake
1639:Haswell
1615:Nehalem
1514:Itanium
1430:Pentium
1425:Celeron
1315:IXP1200
1310:InTru3D
1200:Vantiva
559:cpuinfo
555:in the
414:REAL/32
410:4690 OS
276:In the
83:scholar
3236:Issues
2892:Tarari
2765:Inside
2586:People
2445:XScale
2215:64-bit
2211:x86-64
2116:(2004)
2013:32-bit
1976:80C187
1969:(1980)
1942:(1982)
1936:(1982)
1930:(1982)
1924:(1979)
1918:(1978)
1907:16-bit
1901:Early
1893:(1977)
1887:(1974)
1881:(1972)
1860:(1974)
1854:(1971)
1762:64-bit
1758:x86-64
1608:Penryn
1594:64-bit
1590:x86-64
1549:32-bit
1185:Xircom
1153:Altera
1147:3Dlabs
816:
583:x86-64
557:/proc/
506:paging
454:DOSEMU
333:paging
232:VIA C3
230:mode (
85:
78:
71:
64:
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3262:Other
3073:Hoard
2979:(TLB)
2973:(MMU)
2852:OnCue
2517:PIIXs
2398:Other
2196:Quark
2009:IA-32
1999:80487
1981:80287
1940:80286
1934:80188
1928:80186
1870:8-bit
1843:4-bit
1545:IA-32
1509:Quark
1408:Lists
1344:X25-M
1320:OFono
1132:Intel
1084:(PDF)
998:(PDF)
991:Intel
987:(PDF)
962:(PDF)
926:Intel
840:Intel
637:Notes
626:IA-32
613:AMD-V
545:CPUID
462:NTVDM
450:Linux
446:Merge
440:, in
430:98 SE
368:Usage
295:, or
278:80386
234:only)
160:only)
90:JSTOR
76:books
2692:BiiN
2614:CEOs
2512:ICHs
2507:SCHs
2502:PCHs
2435:i960
2430:i860
2425:RISC
2415:EPIC
2405:CISC
2357:Xeon
2285:Core
2224:Atom
2174:Xeon
2169:Core
2086:Atom
2044:i486
2022:i386
2015:x86)
1967:8087
1955:FPUs
1922:8088
1916:8086
1891:8085
1885:8080
1879:8008
1858:4040
1852:4004
1818:Xeon
1786:Core
1771:Atom
1603:Core
1551:x86)
1504:Xeon
1467:Core
1420:Atom
1360:WiDi
1340:SSDs
1015:here
814:ISBN
760:help
695:2014
553:flag
496:and
470:GRUB
432:and
406:OS/2
297:VM86
154:8080
62:news
2495:Arc
2480:GMA
2229:SoC
2147:III
2137:Pro
2096:SoC
2059:DX4
2054:DX2
2032:376
1951:x87
1903:x86
1839:BCD
1693:ULV
1690:x86
1445:III
1435:Pro
1365:x86
967:AMD
660:DOS
550:vme
541:CR4
534:NDA
466:x86
464:in
458:DOS
374:DOS
349:DOS
228:AIS
134:x86
45:by
3354::
2490:Xe
2234:CE
2142:II
2091:CE
2064:SL
2049:SX
2037:EX
2027:SX
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1558:P5
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