Add Pentium M 780 (SL7VB) support to IC7-MAX3

[u3a6]

Hello everyone!

Ten years ago, and after months of hard work I got enough money to build my first pc which had a Pentium 4 and an Abit IC7-MAX3, I remember that I was really happy when It first booted!

A couple of months ago I had the idea of rebuilding my old pc and I stumbled across this Asus CT-479 socket 479 to 478 adapter, since I had a little bit of spare time and money I got the adapter and a second hand Pentium M 780.

I assembled the Asus ct-479 + Pentium M 780 in my Abit IC7-MAX3 and there was no boot... I started reading a little bit and I was finally in condition to try some bios modding. Keep in mind that I have very little knowledge about how the bios works, so some of the things I tried might seem absurd:

1 - I concatenated the microcodes for the Pentium M PSB533MHz Dothan cpu's (sd6 and sd8 microcode) and injected it in my ic7-max3 bios using CBROM. (I am pretty sure that those are the correct microcodes for the cpu I got)

2 - Using modbin6 I changed the default fsb (100MHz) and nb/cpu strap to the minimum (PSB400) possible, also changed the agp/pci frequency to fixed and disabled Hyperthreading. The cpu volts I left "cpu default". Also tried the same as above but with and FSB of 133MHz and PSB533 which are the correct settings for the Pentium M 780.

3 - I tried some older bios releases, like the first release. I have also tried all the above with the 400 and 533MHz jumper positions in the adapter.

I flashed the bios multiple times including the aforementioned modifications, but I always had the same result: No boot, no post, the board won't even "beep". I tried to boot without ram, and the behavior seems to be the same. I notice that the the hard drive starts to spin and then nothing... I should also add that i can boot with a Pentium 4 using the bios that I modded, so the hardware is in working condition.

I have also found out that are boards that perfectly support the adapter despite not having the I875P chipset or being officially supported (even non asus boards!). I have included a link with the list. I have a folder with the majority of those bios, let me know if you need some more files, other than those that I have included.

I have already put a lot of time into this problem, but I don't have enough knowledge to solve it, this is why I came here to ask for your help, would you kindly look into the problem that I am presenting?

EDIT: The Asus P4C800E-Deluxe and the Abit IC7-MAX3 share the same chipset (i875P) but the Asus uses AMI bios and the Abit Award 6.0. According to the link below the Abit TH7II-Raid boots with the the Pentium M Dothan (allows correct operation despite lacking the microcode) through the adapter (jumper in the adapter at 400MHz position and 533MHz in bios) and despite having the i850 chipset, it has an Award 6.0 bios.

UPDATE: I have been reading the information in Pinczakko's website (https://sites.google.com/site/pinczakko/home). I now realize that the things that I tried with Modbin6 and cpu microcodes were useless. If the system doesn't even beep without ram, so it means that something is wrong in the very early stages of the boot process. CPU is not even getting initialized? Maybe something to do with the reset vector? Would transplant the cpu initialization procedures from the Asus bios solve the issue? I also have 2 spare bios chips, so we have some margin of error.


Files:

Abit IC7-MAX3 bios 18 (Latest bios, i875P chipset, Award 6.0) ->
  IC7P_18.zip (Size: 379.61 KB / Downloads: 1)

Asus P4C800E-Deluxe (before Pentium M support, i875P chipset, AMI) ->
  P4ced19.zip (Size: 407.66 KB / Downloads: 0)

Asus P4C800E-Deluxe (latest with Pentium M support, i875P chipset, AMI)) ->
  P4ced23.zip (Size: 427.32 KB / Downloads: 2)

Abit TH7II-RAID (eh bios, i850 chipset, Award 6.0) ->
  TH7H_EH.zip (Size: 266.28 KB / Downloads: 1)

6d6 and 6d8 microcodes from intel website (Pentium M 780 and PSB533 Dothan cpu's) ->
  6d6_6d8_microcode.zip (Size: 4.66 KB / Downloads: 6)

Links:

Pentium M 780 (Cpu I got) ->http://www.cpu-world.com/CPUs/Pentium_M/Intel-Pentium%20M%20780%20RH80536GE0512M%20%28BX80536GE2266FJ%29.html

Asus CT-479 adapter review -> http://techreport.com/review/8585/asus-ct-479-pentium-m-socket-adapter

List of officially and unofficially supported motherboards -> https://translate.google.com/translate?hl=en&sl=ja&tl=en&u=http%3A%2F%2Fwww.geocities.jp%2Fct_479%2F&sandbox=1

I am aware that this modifications have the potential to damage my hardware and I take all the responsibility.

I am willing to donate to bios-mods.com if you guys come up with a solution, best regards,
u3a6

[u3a6]

I had some more free time at my hands so I researched a little bit more into this issue and I have come to what I think is an interesting conclusion. I downloaded the following datasheets from Intel:

1 - http://download.intel.com/support/proces...526202.pdf - Intel® Pentium® M Processor with 2-MB L2 Cache and 533-MHz Front Side Bus

2 - http://download.intel.com/support/proces...056103.pdf - Intel® Pentium® 4 Processor on 90 nm Process

3 - http://download.intel.com/support/proces...864312.pdf - Intel® Pentium® 4 Processor with 512-KB L2 Cache on 0.13 Micron Process and Intel® Pentium® 4 Processor Extreme Edition Supporting Hyper-Threading Technology

4 - http://download.intel.com/support/proces...988703.pdf - Intel® Pentium® 4 Processor in the 478-Pin Package at 1.40 GHz, 1.50 GHz, 1.60 GHz, 1.70 GHz, 1.80 GHz, 1.90 GHz, and 2GHz

From which i have extracted this informations:
-------------------------------------------------------------------------------------------------------------
Pentium M (Datasheet 1)
VCC,BOOT Default VCC Voltage for initial power up 1.14 (Min) 1.20 (Usual) 1.26 (Max) V

FSB Frequency Select Signals (BSEL[1:0])
BSEL[1] BSEL[0] BCLK Frequency
L H 100 MHz
L L 133 MHz
H L RESERVED
H H RESERVED

VID [5:0] - Vcc V
0 1 1 1 0 0 - 1.260 V
0 1 1 1 0 1 - 1.244 V
0 1 1 1 1 0 - 1.228 V

0 1 1 1 1 1 - 1.212 V

1 0 0 0 0 0 - 1.196 V
1 0 0 0 0 1 - 1.180 V
1 0 0 0 1 0 - 1.164 V
1 0 0 0 1 1 - 1.148 V

VCCHFM3 Vcc at Highest Frequency Mode (HFM) for the Pentium M Processor 780 1.260 V - 1.404 V
VID [5:0] - Vcc V
0 1 1 1 0 0 - 1.260 V (PM - 90nm) / 1.1625 V (P4 - 90nm)
0 1 0 0 1 1 - 1.404 V (PM - 90nm) / 1.3875 V (P4 - 90nm)
-------------------------------------------------------------------------------------------------------------
Pentium 4 130 nm (Datasheet 3-4)

FSB Frequency Select Signals (BSEL[1:0])
BSEL[1] BSEL[0] BCLK Frequency
L L 100 MHz
L H 133 MHz
H L 200 MHz
H H RESERVED

If the processor socket is empty (VID[4:0] = 11111), or
the voltage regulation circuit cannot supply the voltage that is requested, it must disable
itself.

VCCVID VCC for voltage identification circuit –5% 1.2 +10% V

VID [4:0] - Vcc_Max
1 1 1 1 1 - VRM output off
1 1 1 1 0 - 1.100 V
0 1 1 1 1 - 1.475 V
0 1 1 1 0 - 1.500 V
0 1 0 1 0 - 1.600 V

-------------------------------------------------------------------------------------------------------------
Pentium 4 90 nm (Datasheet 2)

FSB Frequency Select Signals (BSEL[1:0])
BSEL[1] BSEL[0] BCLK Frequency
L L RESERVED
L H 133 MHz
H L 200 MHz
H H RESERVED

If the processor socket is empty (VID[5:0] = x11111), or
the voltage regulation circuit cannot supply the voltage that is requested, it must disable
itself.

VID [5:0] - Vcc V
1 1 1 1 1 1 - VRM output off
0 1 1 1 1 1 - VRM output off

0 1 1 1 0 0 - 1.260 V (PM - 90nm) / 1.1625 V (P4 - 90nm)
0 1 0 0 1 1 - 1.404 V (PM - 90nm) / 1.3875 V (P4 - 90nm)
-------------------------------------------------------------------------------------------------------------

This data explains why the cpu works in the Abit TH7II-Raid and does not work in the Abit IC7-MAX3.
The TH7II-raid has the i850E chipset which supports cpu's up to 533MHz. The FSB Frequency Select Signals for the 130 nm P4 cpu´s are L L for 100 MHz and L H for 133 MHz, while for the Pentium M are L H for 100 MHz and L L for 133 MHz. This explains why the TH7II sets the cpu to 533MHz when the jumper in the Asus ct-479 socket adapter is set to the 400MHz position.

The VID selection for the Pentium M and Pentium 4 90nm has 6bit while for the 130nm 533MHz Pentium 4 has 5bit. According to the Pentium M datasheet the VCC,BOOT (Default VCC Voltage for initial power up) should be: 1.14 (Min) 1.20 (Usual) 1.26 (Max) V, which according to the Pentium M VID table would be VID[5:0] 0 1 1 1 1 1 for 1.212 V. According to the Pentium 4 90nm VID[5:0] 0 1 1 1 1 1 would result in "VRM output off" and no boot! For the 130nm 533Mhz Pentium 4 VID[4:0] 1 1 1 1 1 would also result in "VRM output off", since the TH7II boots fine, it means that it is only reading VID[5:1] 0 1 1 1 1 (1) when booting the Pentium M which according to the 130nm 533MHz Pentium 4 VID table would mean VID[4:0] 0 1 1 1 1 - 1.475 V, a possible boot!

I have also compared the VID selection tables for the Pentium M and Pentium 4 90nm and for the same VID vector the Pentium 4 90nm voltages are always lower, which is good, while the 130nm 533Mhz Pentium 4 always has higher voltages.

I think this mod should possible, but unfortunately I do not have the knowledge to find the part of the Asus P4C800E-Deluxe bios that deals with cpu recognition and initialization routines and transplant it to the Abit IC7-MAX3 bios... This is why I am asking for your time!
Best regards,
u3a6

[u3a6]

I was researching a little bit more and I have found out that the Abit uses the ISL6556B pwm controller, while the Asus uses the ADP3180, which have similar specs but the pin configurations are quite different... Would this make the mod any more difficult?

I should also add that I do not care about features like speed step etc... I just want to get the cpu to work at the max power state with the possibility of fsb and voltage adjustments....
Would that be feasible?

UPDATE: I am able to control my Pentium 4's voltage shorting the VID pins with thin copper wires in the cpu socket. Previously I assumed that default Pentium M VID was 0 1 1 1 1 1, so in order to have the proper cpu boot voltage I shorted the VID 5 with VID 2 (VID 5 is below VID 2 in the cpu socket) to get 1.1875V and then I tried VID 5 -VID 2 - VID 1 which would give 1.2375, but still do not get the system to give any signs of life...

UPDATE 2: I have now realized that VCC,BOOT is the same on the Pentium and Pentium M and it just serves the purpose of defining the VID bit vector,it is not the pentium M boot VID as I previously assumed... I must find out what is the default VID at boot on my pentium M. I have also found out that the RESET# signal at boot must be held for at least 1ms for the pentium 4 while it must be at least 2ms in the case of the Pentium M.

ISL6556B datasheet: http://www.intersil.com/content/dam/Inte...l6556b.pdf

ADP3180 datasheet: http://datasheet.octopart.com/ADP3180JRU...t-9161.pdf

Best regards,
u3a6

[u3a6]

I have been reading "The BIOS Disassembly Ninjutsu Uncovered" by Pinczakko. I have been playing around with "IDA Pro" and "Hex Workshop" in order to try to find in my bios de cpu identification and initialization routines. I have also read the "Intel® Processor
Identification and the CPUID Instruction". Unfortunately I do not know anything about the programming language that is used...

I used awdbedit to extract all of the uncompressed bios components and then used IDA pro and the hex editor to take a look into the files. I did find some strings in the main bios file, like:
- Intel Genuine Processor
- Intel Pentiun® 4
- Intel Xeon™
- Intel Xeon™ MP
- Mobile Pentium 4 M
- Intel Celeron®

As far as I know the cpu identification and initialization routines should done right after the power and before the main bios file is loaded?

I expected to find someting in the boot_blk.bin 8kb file, but I was only able to find things related to the floppy drive...

I am sure that the hardware supports the adapter and the mobile cpu, I think this is just a matter of the board refusing to boot due to unkown cpu Family Code and Model Number. Will this have some implications later on with loading the correct microcode?

Would getting a cheap PCI Debug Card help in this quest?

Should I put the Pentium M 780 that I got in a laptop to find the exact CPUID values with CPU-Z or aida64?

Could anyone give some insight?

Best regards,
u3a6

[u3a6]

I am now thinking about using "Bios Patcher" from rom.by... Let it fix the bios, I have no idea about what i should do next, to make this work... Anyone?


UPDATE: I have used Bios Patcher to force the cpu name, (hopping it would change the cpu id code) but it has no worked either... According to the Intel datasheets, the cpu gives info like operating frequency, enable disable HT, cache size, cpu VID etc, it basically gives all the necessary configuration parameters, so that the board can auto detect this stuff and have the cpu properly working. At this moment I strongly believe that the board does not know what to do after it finds a unknown Family Code (1111 for all the supported Pentium 4, Xeon, Mobile P4M and Celeron cpus and 0110 for the Pentium M 780) and Model No. (several Model No. for the P4 family cpus and 1101 for the Pentium M 780). I guess it would also lack the strings to associate the 0110 code with the name Pentium M or something like this... I dont care about the name of the cpu in the bios, could associate any of the other cpu name strings to the Pentium M...

Best regards,
u3a6