Acer MXM BIOS Mods and discussion (was: x920G vs. 9600M GT)

[juodvarnis]

thnx, netroller, i already found your another post with link to this bios, updated, but the card dont work anyway, so i will return it to seller and will take cheaper good ol' gf9600m gt
btw i saw few post here from people with same problem (but still no solution), i doubt that the card is broken

sad, as i work with 3ds max mainly and never had any quadro or firegl card, always modding drivers to force pro capabilities (now hd2600>firegl5600 on w7u 64bit)

starting save money for aspire 3830TG

[.NetRolller 3D]

There is no way you could have saw this BIOS in another post of mine, as I built it right before posting it here today - you've probably downloaded a predecessor of this BIOS, which contained all fixes in this one (Advanced menu, VT enable, SLIC, maybe a few more I've forgotten), except for the MXM fix.
(The easiest way to tell if you are running the correct BIOS is that the MXM-patched BIOS should display "MXM Edition" in green under the Intel logo, when quick/silent boot is enabled. My previous mods display "Advanced Menu Edition", or "Advanced Menu Edition V2" under the logo, while stock Acer BIOS has no text there at all.)

However, it's easily possible that the card is broken - the usual problem with 770M cards in a 5720G is "MXM structure not found or invalid, wait 30 seconds", and not the inability to get a display.

[juodvarnis]

true, that was v2. mxm edition no help. thanx anyway...

[mookill]

well my 9600GT C1 is on its way.
its the DDR2 version which was way cheaper than DDR3.

I couldnt justify paying over $200 USD.

thats half the price of an AMD based Netbook.

will update in a week or so

[lizzarddos]

@mookill You should have gotten the DDR3 version as it is way faster, 1000-1200 3dmarks difference vs the ddr2 version (Just remembering from the top of my head, someone correct me if I'm wrong). If it was me, I'd rather go for the older revision A1 and grab the DDR3. Just my humble opinion

[u6b36ef]

Whether it accepts previously picky cards, like the 9600M GT. I really hope it does NOT break previously working cards - but given that the end of the MXM structure was overwritten with machine code in the original BIOS (requiring me to shorten the structure), it is possible that even the byte that became the new checksum byte was originally code, so regression testing may also be needed.

About the 5920 flash uncertainty.
-Is it that the part of the MXM structure that was missing from from the original SBIOS - is the problem? (Meaning you don't know what original modifications were given to the original MXM structure.) We have seen that the 9920 SBIOS/VBIOS construct is unique, and also the clashing 9500M GS BIOS's. Do you suspect the 5920 standard cards, may have some unique SBIOS MXM structure? I had been kind of figuring the MXM was the mostly meant to be the same for each card, excluding 9920 for example.
-Or is it the command of the checksum byte.

Anyway I have read about Phoenix flashing and discovered some have difficulty in getting boot from USB stick. Is it simply a case of dropping the Phoenix crisis files onto a USB stick, since I don't have a floppy. Once I understand preparation of the USB stick, I'll be OK from there. (I realise VBIOS flash sticks need to be bootable. Yet I can't get the picture of what to do 'exactly' for the Phoenix flash disc preparation, if I need to repair.)

I have a G84 GPU (8600m gt) that I don't mind using for testing. It actually needs oven baking since it has not picture at the moment. If I bake it and then it works, I don't mind if it dies under your BIOS test. I don't want to use the working card I have in use at the moment, (since you think something might break.) Also I have the 9500M GS that doesn't like the current 5920 SBIOS, which I could try with.

[.NetRolller 3D]

About the 5920 flash uncertainty.
-Is it that the part of the MXM structure that was missing from from the original SBIOS - is the problem? (Meaning you don't know what original modifications were given to the original MXM structure.) We have seen that the 9920 SBIOS/VBIOS construct is unique, and also the clashing 9500M GS BIOS's. Do you suspect the 5920 standard cards, may have some unique SBIOS MXM structure? I had been kind of figuring the MXM was the mostly meant to be the same for each card, excluding 9920 for example.
-Or is it the command of the checksum byte.

Neither. The problem is that the code for responding to MXM interrupts, including the one for retrieving the MXM structure, overlaps the MXM structure itself in this BIOS (presumably due to confusion around what the "length" field of the MXM structure means - in v2.x and up, it is the size of the MXM structure in bytes, excluding the header, wheile in MXM v1.x, it was including the header). To overcome this, I made the MXM structure shorter (0x29 bytes data + 8 bytes header), but to achieve this, I had to set the new final byte of the shortened MXM structure (the checksum byte) so that the bytewise sum of the entire structure is evenly divisible by 256 (i.e. the checksum of the whole structure is 0). However, it is possible that the checksum byte itself was also intended to be code, so overwriting it with an actual checksum may have made the MXM interrupt handler nonfunctional.

Anyway I have read about Phoenix flashing and discovered some have difficulty in getting boot from USB stick. Is it simply a case of dropping the Phoenix crisis files onto a USB stick, since I don't have a floppy. Once I understand preparation of the USB stick, I'll be OK from there. (I realise VBIOS flash sticks need to be bootable. Yet I can't get the picture of what to do 'exactly' for the Phoenix flash disc preparation, if I need to repair.)

You do NOT need to do a VBIOS flash, but an SBIOS one. Basically, for a Phoenix BIOS, there is a special "Phoenix crisis disk utility" to create a floppy disk that can be used for recovery. (You need an USB floppy driver for this to work - As far as I know no flash disk or CD/DVD support exists, only floppy.) You can find the necessary tools @ Phoenix Bios Recovery - The Elder Geek on Windows

Also, could you please dump the first 1MB of your system memory using a Linux live CD (with the help of /dev/mem) and post the result here? This would allow me to figure out the exact beginning of the MXM interrupt handling code, and adjust the MXM structure to prevent overwriting any machine code.

I have a G84 GPU (8600m gt) that I don't mind using for testing. It actually needs oven baking since it has not picture at the moment. If I bake it and then it works, I don't mind if it dies under your BIOS test. I don't want to use the working card I have in use at the moment, (since you think something might break.) Also I have the 9500M GS that doesn't like the current 5920 SBIOS, which I could try with.

I'm absolutely sure it won't damage the MXM card - but it may make the laptop unbootable, if I got the end offset of the MXM structure wrong. This is when you may need a crisis recovery disk. (It won't physically damage the motherboard either.)

[u6b36ef]

@ .NetRolller 3D

Yeah I know it's SBIOS flash. I'm stuck at how to make the USB stick ready to go. I saw the 'Elder Geek' link first when I went looking. Since I had no registration with that site (I can't download, so) I continued searching. I copied instructions for SBIOS flashing from four separate sites. They all concurred. Plus I downloaded the software.

[I have a USB drive and the files. Others say they struggled to get USB going and had to resort to floppy drive.]
My question was:
Is the USB to be formatted to a bootable drive 'like' when you make a VBIOS flash drive, or;
Do I just dump the Phoenix Crisis files (+BIOS file) onto a USB drive, then it's good to go?


Quote .NetRolller,
" Also, could you please dump the first 1MB of your system memory using a Linux live CD."
I've never seen this before. Please be patient while I sort it.

[.NetRolller 3D]

As far as I know there should be an executable in the file you downloaded which can generate a crisis disk image from a provided WPH file, that you can then write to a floppy disk with rawrite (or perhaps it writes directly to a floppy disk). You can NOT use anything other than a floppy As far as I know when dealing with PhoenixBIOS - the boot block requires a specially formatted floppy disk for recovery. (USB drives and CDs are As far as I know for InsydeH2O only, perhaps also for AMI or Award.)

About the 1MB dump: You boot up from a live CD, then do "dd if=/dev/mem of=~/memory.dmp bs=1024 count=1024" as root. The dump file will be in ~/memory.dmp.

[u6b36ef]

@ NetRoller 3D, I got message, dd opening '/dev/mem': Permission denied. Am going to keep trying/looking.