Dell OptiPlex GX520 & GX620: CPU Upgrade to P4 and Pentium D

[DeathBringer]

OK. Download SYMCMOS and run in DOS:
SYMCMOS –v2 –lOLD.TXT
Post file old.txt

Code:

usage:                                                  
   SYMCMOS <options>                                    
      -?                show this help                  
      -D                program BIOS default values    
      -S[filename]      produce symbolic report file    
      -L[filename]      produce literal report file    
      -U[filename]      update CMOS using script file  
      -C[filename]      combine build files            
      -F[filename]      use combine file for report    
      -V0               disable logging                
      -V1               enable error logging (default)  
      -V2               enable verbose logging          
      -V3               No CMOS update and verbose logging

[SeñorBIG]

receive an error with no log file generated:

Write literal report to file: OLD.TXT

combineFiles (0h, COMBINE.ROM)...
initPdmEntry ...
search '$PDM' ... not Found!
pdmEntry = NULL !

[DeathBringer]

Do you run in native DOS or command line in Windows?

[SeñorBIG]

through windows. should i run it in pure dos?

[DeathBringer]

Pure DOS only!

[SeñorBIG]

Tried in pure dos with dos running on a usb stick. gives the same error

[DeathBringer]

I found code that verify CPUID and Diagnostic LEDs. On error it set status number 0x16 (Alert! Incompatible processor detected.).

Code:

seg000:7F81 sub_7F81        proc far
seg000:7F81                 pushad
seg000:7F83                 call    far ptr 0F000h:1CD9h
seg000:7F88                 jnz     short loc_7FF4
seg000:7F8A                 mov     eax, 1
seg000:7F90                 cpuid
seg000:7F92                 cmp     ax, 0F30h
seg000:7F95                 jb      short loc_7FF4
seg000:7F97                 mov     ecx, 198h
seg000:7F9D                 rdmsr
seg000:7F9F                 test    eax, 80000000h
seg000:7FA5                 jnz     short loc_7FE7
seg000:7FA7                 mov     eax, 1
seg000:7FAD                 cpuid
seg000:7FAF                 cmp     ax, 0F44h
seg000:7FB2                 jb      short loc_7FCF
seg000:7FB4                 cmp     ax, 0F60h
seg000:7FB7                 jnb     short loc_7FBE
seg000:7FB9                 cmp     ax, 0F49h
seg000:7FBC                 jnb     short loc_7FCF
seg000:7FBE
seg000:7FBE loc_7FBE:                               ; CODE XREF: sub_7F81+36j
seg000:7FBE                 call    far ptr 0F000h:33E9h
seg000:7FC3                 jz      short loc_7FCF
seg000:7FC5                 mov     dx, 8B8h
seg000:7FC8                 in      al, dx
seg000:7FC9                 and     al, 2
seg000:7FCB                 cmp     al, 2
seg000:7FCD                 jnz     short loc_7FE7
seg000:7FCF
seg000:7FCF loc_7FCF:                               ; CODE XREF: sub_7F81+31j
seg000:7FCF                                         ; sub_7F81+3Bj ...
seg000:7FCF                 mov     ecx, 1A1h
seg000:7FD5                 rdmsr
seg000:7FD7                 test    eax, 40000h
seg000:7FDD                 jz      short loc_7FF4
seg000:7FDF                 test    eax, 20000h
seg000:7FE5                 jnz     short loc_7FF4
seg000:7FE7
seg000:7FE7 loc_7FE7:                               ; CODE XREF: sub_7F81+24j
seg000:7FE7                                         ; sub_7F81+4Cj
seg000:7FE7                 push    cx
seg000:7FE8                 mov     cx, 16h
seg000:7FEB                 call    sub_9B4A
seg000:7FEE                 pop     cx
seg000:7FEF                 call    far ptr 0F000h:0A497h
seg000:7FF4
seg000:7FF4 loc_7FF4:                               ; CODE XREF: sub_7F81+7j
seg000:7FF4                                         ; sub_7F81+14j ...
seg000:7FF4                 popad
seg000:7FF6                 retf
seg000:7FF6 sub_7F81        endp

But I can't edit BIOS But I found reason why this warning is occur on one board and don't on other. It's diagnostic chip that control Diagnostic LEDs.
BIOS with Pentium D always check value in I/O port with address 0x8B8.

[SeñorBIG]

maybe some of the guys from the dell section can help?

https://www.bios-mods.com/forum/Forum-Dell

[DeathBringer]

I don't think so.
Try this:
1.Restart your computer and tap F12 at Dell logo.
2.Select 'Diagnostics' and hit Enter.
3.Make a note of error code if any.

[SeñorBIG]

my system only has hard drive diagnostics