ASUS A7S8X-MX tweak

[idcarlos]

Hi.

One year ago my Asrock K7S41GX fails (I burn something in the onboard sound card), and I buy a ASUS A7S8X-MX that is the same MB but with better sound card and serial ATA

But the BIOS suck! no overcloking features!
In my Asrock I have the FSB at 200, higher than the MB and chipset especification, but you can put the values in the BIOS and it's WORKS!

I recently discover the modbin6 tool. I change the hidden values to tweak de FSB and now I have the FSB to 199.

There is the bios ver 1007 modified

And the question are:
1.-How I can change the higest value of the FSB (it's limited to 199)
2.-With other bios i can tweak the onboard VGA clock ¿any idea?
3.-Any othe sugestion to tweak this BIOS?

There are the componets

Code: Select all

================================================================================
  0. System BIOS       20000h(128.00K)12559h(73.34K)1007.BIN
  1. XGROUP CODE       0D730h(53.80K)09305h(36.75K)awardext.rom
  2. ACPI table        03D4Eh(15.33K)016F2h(5.74K)ACPITBL.BIN
  3. EPA pattern       0168Ch(5.64K)002AAh(0.67K)AwardBmp.bmp
  4. YGROUP ROM        06C50h(27.08K)04695h(17.65K)awardeyt.rom
  5. GROUP ROM[ 0]     07880h(30.12K)03081h(12.13K)_EN_CODE.BIN
  6. Flash ROM         0AAE3h(42.72K)05D2Bh(23.29K)awdflash.exe
  7. VGA ROM[1]        08000h(32.00K)04147h(16.32K)741B1.rom
  8. PCI driver[A]     0A000h(40.00K)0612Ch(24.29K)PXE_M.BEV
  9. LOGO BitMap       2443Ch(145.06K)017B7h(5.93K)asuslogo.bmp


Un saludo
Carlos Garces

[cp]

1. The highest value of FSB is determined by the PLL used on the mainboard. Even if the BIOS shows values that would go beyond that. Did you try to set the jumpers FSB_SEL0 & FSB_SEL1 to 2-3 ? Maybe that will give you 200MHz FSB at startup.
2. Maybe PowerStrip allows you to change the ECLK, you might give it a try. The onboard VGA's Engine Clock (ECLK) is set by a PLL that's inside the SIS Chipset. This PLL is controlled by registers that hold the values for the clock. As SIS (and all others, except Intel) doesn't publish ANY documents anymore it would be pure guessing which registers are used. If there's no option in the BIOS you're stuck to setpci on Linux or wpcredit on Windows. A suggestion on how to find out about the registers involved is at the end of this post.
3. You could use ClockGen to tweak the FSB further.

How to find out about the registers involved in ECLK:
Get a K7S41GX and set up everything to normal. Boot a Linux rescue CD and make a register dump of the VGA device. Reboot and set a different clock in the BIOS, boot the rescue CD again, make another register dump and take a look at the changes. Most PLLs work like this: fout = fref * (N+1) / ((M+1)*(P+1)), where M, N, P are the register values and fref is a reference clock (14.31818MHz is very common).

[idcarlos]

Thanks for the quick reply

1. The highest value of FSB is determined by the PLL used on the mainboard. Even if the BIOS shows values that would go beyond that. Did you try to set the jumpers FSB_SEL0 & FSB_SEL1 to 2-3 ? Maybe that will give you 200MHz FSB at startup.

Setting the jumpers FSB_SEL0 & FSB_SEL1 to 2-3 has no effect, 166 FSB at startup.

I don't like software tweak, because I use 3 different O.S. in the computer.

Un saludo
Carlos Garcés

[cp]

there is/was a bios editor out there for the SIS315 (the VGA core of the SIS741). As you have an integrated solution you could inject a hacked vga bios into the mainboard's bios. Extract the vga bios and disassemble it. Find the calls where the clock values are loaded into the chip. According to this the engine clock data can be accessed via port 3C4 0x2E upto 0x30.

[idcarlos]

Hi.

Unable to find sisutil.exe

Maybe change the FSB and the EPA logo is enough for me, disassemble he VGA Bios without a tool and a guide for lamers its maybe a high risk.

Un saludo
Carlos Garcés

[idcarlos]

Hi.
I have found the last onboard VGA BIOS (2.28.00)
This fix a bug with 1440x900 resolution.
It's safe to extract the VGA BIOS from FOXCONN K7S741GXMG-6L and put it into a ASUS A7S741X-MX BIOS?

Un saludo
Carlos Garcés

[cp]

latest vga bios for the sis741 is 0.85.00 dated 11/26/03. the vga bios file in the foxxconn bios is 0.65.00. get the latest bios files from SiS..they include them in their driver packages to be TSR loaded in windows. you can inject the latest vga bios into the bios with cbrom. happy modding ;)

[idcarlos]

Hi.

I have confused with BIOS version numbers.
SIS has fix this bug with version 2.28.
If I go to Control Pannel"->"Display"->"Settings"->"Advanced"->"Administrator"->"Product information" I see 2.03.

In the VGA BIOS of ASUS I can read with a HEX editor

Code: Select all

SiS Silicon Integrated Systems Corp. 6330 2.03.00

In the FOXCONN

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SiS 6330 AGP True Color Graphics and Video AcceleratorBytes Video Memory, BIOS Version 0.69.00.

And about the BIOS in the driver page... I have 3 oemrom.bin files, but i'm not sure that are a 6330 BIOS.

Maybe the more safe option is extract the bios fom a SIS741GX motherboard ¿What do you think?

Un saludo
Carlos Garcés

[cp]

download univga3 3.76, look into \3.76logo\WinXP_2K\ there you'll find what you're looking for. i don't know what Asus did to the version string.. did you check the date code, too?

[idcarlos]

Thanks.

¿What do you think?, ¿it's safe to change the VGA VIOS with cbroom like the EPA logo?

Un saludo
Carlos Garcés

[edwin]

If you can fit an external video card in there you might be able to recover the thing when it doesn't work out. I have never seen this before so it's entirely at your own risk.

[cp]

i've done this may times before (maybe i've should have stated that earlier ;)) on various boards and bios. my first attempt was a PCChips M717 where i injected a SIS6326 bios for the onboard vga (not integrated though). after that i updated the vga bios every time i got my hands on a board with onboard or integrated vga. most of them were SIS, some VIA and none of my attempts failed :) so give it a go..but don't expect miracles (like twice the speed of the vga or things like that).
just like edwin already stated: if you accidently choose the wrong vga bios then you'll be able to boot with a pci vga card and reflash.

[idcarlos]

but don't expect miracles (like twice the speed of the vga or things like that).

Thanks
This new bios fix know a bug (and maybe more thinks), and ASUS don't release a new version.
To improve the speed of the VGA I can change the core clock (I have found it in a hidden option, located outside the visible menus).

I'll flash it now.

[idcarlos]

I can't update the bios.
Fails because I don't have free space in BIOS (I have only 3,9KB).

The are the files:

741b1.rom----32KB, from ASUS MB, old version
sis741.bin-----64KB, from drivers package
741b1.rom----48KB, from FOXCONN MB, not the last version but fix the bug.

ASUS rom need 16.32KB (50% compression), FOXCONN 25,79KB
I need 25,79-16.32-3,9=5.57KB of space.

I can change the EPA logo and de asuslogo to a black (empty) ¿any other idea?
¿Why the last SIS bios is so big?


Un saludo
Carlos Garcés

[idcarlos]

Hi.
There are my test

Original BIOS from ASUS A7S8X-MX, VBIOS ->2.03, FSB auto.

1007Mod BIOS

-VBIOS 2.13 from ECS 741GX-M, not fix the SIS bug but I'm sure that it's newer than 2.03.
-FSB unlock, tested at 199 with SEMPRON 2200+
-ASUS full screen logo changed by a black screen to get free space on the bios.

Other possible modifications.

-Flash VBIOS 0.69 from FOXCONN K7S741GXMG-6, This VBIOS is tested and works, but I'm not sure that is newer than 2.13, I don't know why version numbers are deferents.
-Get more free space and flash VBIOS 0.85... I can't get more space.
-Change other default vales with MODBIN6, at you own risk.

-DRAM CAS Latency (tested, but my cheap DRAM fails)
-VGA Clock (untested, maybe later)

-Move hidden values to the menu tree to change it in the BIOS. Untested, may corrupt the BIOS...

Un saludo
Carlos Garcés