Dietmar

May be this is a more elegant way, because it sets the last bit in ah always to 1, no matter what has been there before and does not change any other bit in ah and gives the same result as the test, if the last bit in ah is 1 Dietmar .text:0031F3CB call sub_315CDC .text:0031F3D0 or ah, 1 .text:0031F3D3 jnz short loc_31F3E0 .text:0031F3D5 ; --------------------------------------------------------------------------- .text:0031F3D5 push 238Ch .text:0031F3DA call sub_323C94 .text:0031F3DF pop ecx

@Mov AX, 0xDEAD I try to hack the question about CPUID and CMPXCHG8B in setupldr.exe from XP SP3 on the xp.iso. I search via the debug version of this setupldr.exe, but changes I do in the free version of setupldr.exe. Still I get this crazy message about no CPUID CMPXCHG8B on this 486 compi and I have no idea, from where it comes. This I have changed in setupldr.exe. Thanks for help Dietmar .text:0031D48F loc_31D48F: ; CODE XREF: SlInit(x,x,x)+195j .text:0031D48F call _SlInitDisplay@0 ; SlInitDisplay() .text:0031D494 call _BlIs386@0 ; BlIs386() .text:0031D499 test al, al .text:0031D49B jz short loc_31D4A8 .text:0031D49D push 236Dh .text:0031D4A2 call _SlFatalError .text:0031D4A7 pop ecx .text:0031D4A8 .text:0031D4A8 loc_31D4A8: ; CODE XREF: SlInit(x,x,x)+1AEj .text:0031D4A8 call _BlGetFeatureBits@0 ; BlGetFeatureBits() .text:0031D4AD test ah, 1 .text:0031D4B0 jnz short loc_31D4BD .text:0031D4B2 push 238Ch .text:0031D4B7 call _SlFatalError .text:0031D4BC pop ecx ==> .text:0031D48F loc_31D48F: ; CODE XREF: SlInit(x,x,x)+195j .text:0031D48F call _SlInitDisplay@0 ; SlInitDisplay() .text:0031D494 call _BlIs386@0 ; BlIs386() .text:0031D499 test al, al .text:0031D49B jmp short loc_31D4A8 .text:0031D49D push 236Dh .text:0031D4A2 call _SlFatalError .text:0031D4A7 pop ecx .text:0031D4A8 .text:0031D4A8 loc_31D4A8: ; CODE XREF: SlInit(x,x,x)+1AEj .text:0031D4A8 call _BlGetFeatureBits@0 ; BlGetFeatureBits() .text:0031D4AD test ah, 1 .text:0031D4B0 jmp short loc_31D4BD .text:0031D4B2 push 238Ch .text:0031D4B7 call _SlFatalError .text:0031D4BC pop ecx

For to overcome my ultraslow IDE HD with 7 (!) MByte/s I bought this adapter https://www.amazon.de/gp/product/B00EOJNGC2?ref=ppx_pt2_dt_b_prod_image So, from tomorrow starts fun, because this adapter works also with SSD and 6 Gbit/s Dietmar

@jacer4 Here is the new link for this file, good luck Dietmar https://ufile.io/p07xouxv

@user57 Not really. I have only 256 KB Cache Ram chips. With this, I can use with "Write Through" only 64 MB from the 256 installed MB. This you can see in Task Manager. XP shows the full 256 MB, but now uses only the cached 64MB from it. I order from China 1024 KB Cache chips for few Euro, but they arrive here only in May Dietmar PS: I notice a funny behavior: When I make a first try to install XP SP3 on a 486 cpu, this works but later I get a message, that "NULL" was not found, but the 486 compi works. Via this way, in "System" no entry for cpu or ram. But when I use the install from my Asrock z370 k6 board, it shows the correct ram and also the correct 100MHZ 486 cpu from AMD. And I notice, that there exists at least 2 different IDE controller for the Shuttle Hot 433 board, vers. 1..3. They are NOT compatible. One uses ESDI IDE(???) and the other the normal IDE. So, I can not make a generic XP SP3 here for all of them for download, because I have only one harddisk with 8.4 GB and so everything for this needs to be done at least 2 times.

This works nice as much as possible. With this Emulator, XP SP3 on any 486 cpu is now real. I played Pin ball and just now I am installing there Moorhuhn Dietmar

Yessaaaa, now the simulation of cmpxchg8b is much better, here in ntoskrnl.exe Dietmar New ntoskrnl.exe for 486 compi https://ufile.io/3e0u7qi7 .data:004762F2 ; Exported entry 8. ExInterlockedPopEntrySList .data:004762F2 ; Exported entry 36. InterlockedPopEntrySList .data:004762F2 .data:004762F2 ; =============== S U B R O U T I N E ======================================= .data:004762F2 .data:004762F2 .data:004762F2 public ExInterlockedPopEntrySList .data:004762F2 ExInterlockedPopEntrySList proc near ; CODE XREF: sub_40E06D+1DAp .data:004762F2 ; sub_41159B+8Ap ... .data:004762F2 push ebx ; ExInterlockedPopEntrySList .data:004762F3 push ebp .data:004762F4 mov ebp, ecx .data:004762F6 .data:004762F6 loc_4762F6: ; DATA XREF: .text:loc_40A835o .data:004762F6 ; KiDeliverApc+12o .data:004762F6 mov edx, [ebp+4] .data:004762F9 mov eax, [ebp+0] .data:004762FC .data:004762FC loc_4762FC: ; CODE XREF: ExInterlockedPopEntrySList+18j .data:004762FC ; ExInterlockedPopEntrySList+23j .data:004762FC or eax, eax .data:004762FE jz short loc_476317 .data:00476300 lea ecx, [edx-1] .data:00476303 .data:00476303 loc_476303: ; DATA XREF: sub_40A552:loc_40A55Bo .data:00476303 ; .text:loc_40A747o .data:00476303 mov ebx, [eax] .data:00476305 .data:00476305 loc_476305: ; DATA XREF: KiDeliverApc+1Bo .data:00476305 lock cmpxchg [ebp+0], ebx .data:0047630A jnz short loc_4762FC .data:0047630C push eax .data:0047630D mov eax, edx .data:0047630F lock cmpxchg [ebp+4], ecx .data:00476314 pop eax .data:00476315 jnz short loc_4762FC .data:00476317 .data:00476317 loc_476317: ; CODE XREF: ExInterlockedPopEntrySList+Cj .data:00476317 pop ebp .data:00476318 pop ebx .data:00476319 nop .data:0047631A nop .data:0047631B nop .data:0047631C nop .data:0047631D nop .data:0047631E nop .data:0047631F retn .data:0047631F ExInterlockedPopEntrySList endp .data:0047631F .data:0047631F ; ---------------------------------------------------------------------------

@roytam1 On my Asrock z370 k6 board with 8700k cpu all my files without any cmpxchg8b are stable. But this is not the case for the 486 cpu. Strange. I think, it depends only on the simulation of cmpxchg8b in ntoskrnl.exe in the function ExInterlockedPopEntrySList. But I dont have a better idea until now for this simulation of cmpxchg8b there Dietmar

Here are 2 photos of my Shuttle Hot 433 board, with running full XP SP3 on it. I notice, that even from version 1...3 of this board, they have different IDE controllers, so you cant switch from one board to next with the same XP SP3 installation. This strange behavior I have never seen for any IDE controller before. Next step is to build an full Setup XP486.iso. I make a try, to overcome also there the crazy opcode cmpxchg8b and also the "Unknown Processor" hurdle. Any help is welcome, which files on the xp.iso have to be changed, for to kick out those checks. It is not so much difficult I think. My files without any cmpxchg8b are quite stable, anyway I will update them and I also make an english version Dietmar

Hi, does somebody know, where the question about cmpxchg8b "is there" in the XP.iso happens during Setup? And also the same for CPUID. May be, we can take a look at the XP SP1 source files for this question. I do a check, why my XP SP3 was so slow on the Shuttle Hot 433 board with AM486DX4-S cpu with 100 MHZ. Oh, XP SP3 gets only 32 MB from the 256 MB installed memory, I think, because of only 256k Cache. And half of memory because of "write-back" whatever this means for Cache^^.. (should be full memory with Cache settings to write-through) So lets have some more fun with an install xp.iso for 486 cpu, 256 MB ram at 180 MHZ Dietmar

@roytam1 I check careful: No cmpxchg8b is in this file D3DCompiler_43.dll Dietmar

@roytam1 I can try, just send it to me Dietmar PS: Cpu load always 100%. It is stable but slowww..

@roytam1 Yesssssaaa, I got it, XP SP3 on my Shuttle Hot 433 board and AMD 100MHZ 486 cpu Dietmar PS: Boot time to desktop is about 2 min. Via F8 you have to enable VGA modus. New ntoskrnl.exe with modd from @roytam1 https://ufile.io/peux59x6

@roytam1 Windbg session in that x86 box? 1.) Very early Bsod 0x0000005D, (unknown processor), no running bar of XP. 2.) My serial connection does not work for this board. May be, because it does not use the standard configuration 0x3F8, IRQ 4 for the COM1 port. Dietmar

@user57 Until now I do not succeed to set up a Windbg session on my 486 board for XP SP3. May be, that the address of the COM1 port does not match? And I start to think, that not the CPUID of the 486 cpu is the reason for crash Dietmar

@Mov AX, 0xDEAD I think, I get reboot of my modded XP SP3, because of CPUID check in ntoskrnl.exe, opcode 0F A2. Do you know, how to fake this, Dietmar

@roytam1 Thanks, I will check Dietmar EDIT: No one from this files is on my XP SP3 install.

@Mov AX, 0xDEAD Is there a PCI Lan card, that works for Windbg on XP on a 486 board Dietmar

@Damnation Yes, it is a problem, how the harddisk is formatted. Use RMPrepUSB for this with settings ntldr, ntfs, force LBA Dietmar

Here is the for now last modded and tested file for 486 compi Dietmar oledb32.dll https://ufile.io/ygc0ewyl

Here is the file, which I thought before, it was only in Cache, but mistaken. Works now, has to be added: Programme\Gemeinsame Dateien\System\Ole DB\msdatl3.dll for 486 cpu Dietmar msdatl3.dll https://ufile.io/885h39fd

Now, its time for the last one, working wmvcore.dll without any lock cmpxchg8b qword ptr [esi] Dietmar wmvcore.dll https://ufile.io/tor52hvo Whole fun https://ufile.io/yn65co18

Here is working txflog.dll, now without any lock cmpxchg8b qword ptr [esi] Dietmar txflog.dll https://ufile.io/65bujlre

@pappyN4 Hi, I test all 3. None works. duser.dll_EN_5patchandchecksum_virtsizechange BSOD very early, no running bar duser.dll_EN_5patchandchecksum_virtsizechange_rebuildPEheader asks for Password, Device Manager not working duser.dll_EN_5patchandchecksum_virtsizechange_rebuildsize asks for Password, Device Manager not working Wish you a nice day Dietmar

And here is msdtctm.dll, also now without any lock cmpxchg8b qword ptr [esi]. Tested, working Dietmar msdtctm.dll https://ufile.io/vmc20tgu