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0neWinged
06-11-2016, 05:04 PM
Alright so I have an Asus G75vw with a GTX 660m. I bought a GTX 780m and heatsink from a G750jh. I did some chassis modifications and managed to get everything to fit. Flashed new bios with vbios of 660 and 780.
I turned off UEFI prior to flash, turned UEFI off prior to card swap. Laptop fired up, but boots to Asus boot logo screen, (where you would normally access bios) but gets stuck. I cannot access bios. Trouble shooted a few things, but still no luck. Even swapped back to the 660m and boots passed the boot screen. So I then re flashed to my stock bios, and tried swapping to 780m to see if it wouldn't show the boot screen, but it does the same thing.
So.. From what I am told it is trying to load the VBIOS onboard of the 780M PCB. Also was told It definitely is a module regarding PEG control. This should be in the unlocked "Chipset" tab, but as I've mentioned a while back, this is where things can bjork the boot block and even the recovery block if a setting you enable is deep BIOS disabled.. (no supported callback module) meaning, ICSP programmer is the only way out of it. (Don't want to brick or have to find a ICSP programmer).
Any insight would be appreciated. I also have this up at WIN RAID forum as well, but figured it can't hurt to have more eyes and brains.
In the end, I just want this thing to recognize the 780 as its card and boot. I already have modified drivers, just need a successful boot.
Anyone willing to help with this modification will be highly highly appreciated.
Thanks!

jmhdj
06-12-2016, 11:41 AM
Hi. As I remember correctly G75 series has vbios inside of main system bios. Correct me if I am wrong. Did you remove completely 660m vbios from bios or just added 780m vbios on top?
Did you tried 780m with UEFI enabled?
Where did you got 780m vbios you inserted inside bios?
Is it asus 780m vbios?

0neWinged
06-12-2016, 05:24 PM
Hi. As I remember correctly G75 series has vbios inside of main system bios. Correct me if I am wrong. Did you remove completely 660m vbios from bios or just added 780m vbios on top?
Did you tried 780m with UEFI enabled?
Where did you got 780m vbios you inserted inside bios?
Is it asus 780m vbios?

Ah the man I've been waiting to hear from!! Lol
Yes G75 does have vbios inside of main system bios.
I have been working with Dreamonic up to this point and talking with him on his site voltground. I dumped my bios and I uploaded to him. Which has 660m and 670m vbios. He removed 670m vbios and replaced with 780m. So the newly modified bios has 660m and 780m vbios.
I did try 780m with UEFI enabled, still same result, stuck at ROG boot logo.
Dreamonic had the 780m vbios and I'm almost positive he used Asus 780m vbios.
Im worried to flash only 780M Vbios as I may get stuck trying to revert due to the fact I cant access bios or boot menu with 780M installed and probably not be able to access bios or boot menu with 660M installed

Ill inform him of this thread so he can pitch in too. Hes smarter than I am on this bios mod subject and would be able to provide better details than me. Ill have out convo points uploaded as they are PM and not a thread so I can provide a link. Ill also provide links for all bios/vbios .rom files that were used.


==> Stock G75VW System Bios (https://app.box.com/s/w1rcb61pgt358n1f9an7h26gesi2bk4t)
==> Stock G750JH 780M VBIOS (https://app.box.com/s/ll96bt96awzyzoku9vt1daitp7ev9f8w)
==> Modified G75VW Sytem Bios With 660M & 780M VBIOS (https://app.box.com/s/7cn6jr8odo7ujrqg166e2j03pehg7v7q)


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jmhdj
06-12-2016, 05:53 PM
Dont know what to say as I havent mod anything beyond asus G73 models. You would have better chance for help from dreamonic if you could take whole bios dump. Only way to get whole dupm is to desolder bios chip and read it with soic reader.
What could be another route is to see if there are different revisions of asus 780m vbios.

Dreamonic
06-12-2016, 06:05 PM
It is indeed the ASUS 780M VBIOS and no, flashing with just the 780M OROM isn't going to help at this point as the VBIOS onboard the 780M is definitely being used. My guess is it's either PEG control/BUS interface as the system BIOS callback is to the OROM for the GPUs in the G75 unlike the G750. However, with just the 780M installed with nothing else done, the display still actually works too. The fact it's preventing BIOS access leads me to believe it's certain callback modules that the G750 has for read/write (0xFF) access to the BIOS chip onboard its PCB through ASUS MXM structure as faults have been detected. I believe those correct modules are the LegacyRegion2 (G750) and PciExpressDxe (G75) modules and a couple others. It's now getting to a point where it can potentially corrupt the boot block and recovery block should it not succeed (requires HW programmer) through experimentation.

EDIT: Now I understand jmhdj, you've done the G73JH that has only the ATI GPU HW callbacks with the G73SW that has only the NVIDIA GPU callbacks. This I understand. What is strange with our modification is the MXM GPU > OROM > System BIOS in the G75 to the MXM GPU > GPU VBIOS (onboard) > System BIOS (no OROM) in the G750. Since one reads differently than the other yet the display is still being initialized... that's the part I'm trying to figure out. That means the VBIOS is correct but modules in the system BIOS are not configured for it.

Dreamonic
06-12-2016, 06:12 PM
I wonder if shorting (prior to boot - temporarily) the 780M BIOS chip to bypass it would allow the read of the OROM (VBIOS inserted) instead...

jmhdj
06-12-2016, 06:16 PM
Sounds like logical and probably correct diagnosis. As for which modules inside system bios are responsible your gues is better than mine :)
Wish you best luck further.
Will watch over this thread and if I get any ideas will post them.

jmhdj
06-12-2016, 06:18 PM
I wonder if shorting (prior to boot - temporarily) the 780M BIOS chip to bypass it would allow the read of the OROM instead...

It cant hurt at all, as long as he dont short something other :)

jmhdj
06-12-2016, 06:21 PM
If I remember long time ago other guy tried to upgrade his G53 with asus 780m gpu and we found that asus 780m is mechanicaly different from standard mxm 3.0 gpu's.
Will check on this as I am not sure my recolection is good.

Dreamonic
06-12-2016, 06:34 PM
They do have their own proprietary PCB design but the MXM connection shouldn't have changed according to this:

MXM Version 3.0 Technical Brief
MModule Concept

The MXM version 3.0 specification allows system designers the flexibility to customize the module
in a OEM shipping configuration. The MXM version 3.0 specification achieves this goal by allowing
the freedom to use OEM-specific, non-compliant, modules in an MXM version 3.0 compliant system.
Common scenarios are:

Form Factor

OEM modules are allowed to use non-standard form factors as long as the system can
accommodate MXM version 3.0 standard modules.

VBIOS ROM

OEM modules are not required to have a ROM chip as long as the system can correctly
operate using a standard MXM version 3.0 module with on-board VBIOS ROM.

Power

OEM modules can rely on additional voltages supplied by the motherboard. OEM reserved
pins are provided by the specification. All MXM version 3.0 compliant modules will not connect
these pins.

Extra Signals

OEM modules are allowed to use extra signals provided by the motherboard. OEM
reserved pins are provided by the specification. All MXM version 3.0 compliant modules will not

Dreamonic
06-12-2016, 07:04 PM
You ended up using the ASUS VBIOS with your G73SW GPU upgrade didn't you? Even though the GPU you used was that of another manufacturer because it allowed it to boot with the best results.

The G73's use OROMs though. The card you purchased, a standard MXM 3.0b GPU obviously had the other manufacturer VBIOS onboard. So I suppose these two mods are similar in that, yours was in fact OROM supported initially (G73SW) but used the onboard VBIOS in the end with a GPU manufacturer other than with the ASUS MXM GPUs but with their VBIOS?

I see what you're referring to now, ASUS GPU HW could be the problem with the upgrade in another system.

0neWinged
06-12-2016, 07:37 PM
At this point im willing to try anything as long as its not permanent fail or have a fail safe.
As far as soldering, im pretty good but that bios chip is Tiny. Micro soldering at a whole new level and I dont have that kind of equipment or skill.
both cards are MXM 3.0 and have exact same pin layouts.

Just thinking here, but is it maybe possible to modify this card via hardware? hook it up externally to a desktop and have read/write access?
how can I go about stopping/bypassing (shorting) the vbios on the 780m?

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0neWinged
06-12-2016, 07:58 PM
To bad I cant find an Asus hardware specialist to diagnose this issue. compare the two builds and be able to specify.
I get it, Asus doesn't want you upgrading, they rather make money and you buy a new PC. Much more fun and satisfying to get something working in something where it doesn't belong

Dreamonic
06-12-2016, 08:10 PM
That kind of adapter actually exists (cool). No mention whether or not it works though with multiple vendors: http://www.pcidv.com/products.asp?id=628
(http://www.pcidv.com/products.asp?id=628)
To short temporarily, follow what I did in the picture below. You'll want to flash back to the M660780.ROM before doing so. Hopefully once it's temporarily disabled (bypassed) it may allow the OROM to be initialized. I'd recommend to use something of similar thickness of the pins used with the BIOS chip. Only touch the two pins in the diagram and those pins only! Do so before powering up with the AC adapter disconnected. Once those pins are bridged (keep it like that for the duration of the test) then plug AC adapter back in and power on the system.

Dataesheet: http://html.alldatasheet.net/html-pdf/178189/WINBOND/W25X40/1489/5/W25X40.html

0neWinged
06-12-2016, 08:20 PM
Ill give it a go and see. hoping for the best. May the GPU gods be in my favor, lol

0neWinged
06-12-2016, 09:20 PM
bread tie wire cut and bent to size. Was a touch to thick to fit between the chip and wire, so I crimped down with some tweezers and took a metal grinding disk and shaved off by hand. Did both sides. Lined up to the chip and snugged it in with a razor blade.
Now comes the real test. swap and boot.
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0neWinged
06-12-2016, 09:42 PM
That kind of adapter actually exists (cool). No mention whether or not it works though with multiple vendors: http://www.pcidv.com/products.asp?id=628
(http://www.pcidv.com/products.asp?id=628)
To short temporarily, follow what I did in the picture below. You'll want to flash back to the M660780.ROM before doing so. Hopefully once it's temporarily disabled (bypassed) it may allow the OROM to be initialized. I'd recommend to use something of similar thickness of the pins used with the BIOS chip. Only touch the two pins in the diagram and those pins only! Do so before powering up with the AC adapter disconnected. Once those pins are bridged (keep it like that for the duration of the test) then plug AC adapter back in and power on the system.

Dataesheet: http://html.alldatasheet.net/html-pdf/178189/WINBOND/W25X40/1489/5/W25X40.html

DUDE!!!!! You are what I call a Fu**king GODSEND!! G75VW with GTX 780M Booted into Windows Success!!!!!!!!!!!!!!!
Major break though and accomplishment! Thank you all for coming to the show
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0neWinged
06-12-2016, 09:53 PM
So is this bridge something I should make permanent now that it is required for boot? I believe I should be able to solder those 2 points since Ill have room because its on the end.
Now im going to finish up the heatsink plate, get this thing down with some Gelid extreme and get some custom drivers booted.

Dreamonic
06-12-2016, 09:59 PM
That's absolutely a breakthrough buddy! The time being, do some tests and monitor temps and voltage first then plan on making a permanent bridged connection.

EDIT: It looks like the modules for MXM GPU > OROM can still be successful even with VBIOS onboard the GPU already. This means a lot more GPU upgrading opportunities than ever before now.

Let me know how the rest goes!

https://cdn.meme.am/instances/62577932.jpg

0neWinged
06-12-2016, 10:14 PM
That's absolutely a breakthrough buddy! The time being, do some tests and monitor temps and voltage first then plan on making a permanent bridged connection.

EDIT: It looks like the modules for MXM GPU > OROM can still be successful even with VBIOS onboard the GPU already. This means a lot more GPU upgrading opportunities than ever before now.

Let me know how the rest goes!

https://cdn.meme.am/instances/62577932.jpg

Absolutly! I started a new thread based on success story since this is no longer a Deep bios mod required.
Ill be doing some tests and follow up with some serious information and benchmarking.