Custom underclocked vBios rom for FX-7811u 9C.23.00 - might solve black screen problem for u

Hi,

I recently purchased a used FX-7811u, I must say I really like it.
After several days of use I noticed that during gameplay I would often get black screen with sound loop. After I googled it I saw its a common problem with the 9800m gts graphic card, so I decided to try and play with the clock speed and voltage to see if it has any affect, after several tries I found that in order to preserve stability I have to downclock the gpu quite a bit, but it still give good performance.

Anyway, I compiled this bios with conservative settings - all modes are as usual and for extra mode - 0.95v gpu - 495mhz, mem - 550mhz, shader - 1100mhz

This is a complete system bios which also includes within it the custom vBios.
Its only for use on 7811u, to flash it make a bootable dos usb or cd and copy the files.
just run bios.bat and follow the instructions.

It goes without saying that if you don't know what you are doing you might brick your notebook!!!

FX7811_9C.23.00_Underclocked.rar

 

I just started using this forum looking for an undervolt solution to my 7811, and I am so happy that you are sharing this! It's even .23! I was thinking of selfishly asking for one without the underclocks, but I think I can take care of that with the nvidia tools.

Thanks!

 

Here you go, this one is just as the original 9C.23 except that for extra mode it uses 0.95v.

Note that some people claim that the voltage can't be changed through the bios and in fact the bios just report that its using 0.95v when in fact it uses the original 1.11v. I'm not sure about that myself, haven't tested it thoroughly.

Anyway here is the link for the bios, same drill as before...

FX7811_9C.23.00_0.95v.rar

 

Thanks for the work on that 2nd one, but my GPU reports 1.11V with it. It reports 0.95V at all times with the first BIOS (which I think puts it over stock by 0.05V at idle). Strange. Also, it might just be GPU-Z, which seems to make my GPU run at 3D speeds on the desktop.

 

It does seem that it just reports the custom voltage when in fact it uses the original one.
I have some stability issues with any voltage other than 0.9v even when I underclock by this much, so I made a new custom bios with 0.9v for the extra mode with the following clocks - GPU core - 490mhz. Shader - 1100mhz, vram - 540mhz. This one seems stable so far, tested it on Call of Duty: Black Ops and Crysis Warhead, its also runs cooler.

It seems that GPU-Z forces the GPU to extra mode in the first few seconds after you run it and slowly go through the GPU modes.

here is the link for the new bios:

FX7811_9C.23.00_0.9v.rar

 

Keep in mind when overclocking and underclocking every chip is different, just as some peoples notebooks run hotter than others when they have the exact same config, some chips will not run stable undervolted where others are.

I have a few suggestions for you.
-I don't think its necessary to downclock the vRAM that much. Many cards have vram rated above the stock clock anyway.
-Have you tried undervolting without downclocking as much? There have been reports of some cards that actually run at higher clocks when undervolted.
-What you are saying about GPU-Z reporting the custom voltage but it still running at stock could easily be possible, this is a limitation of voltage ICs which usually have much less modes than are presented in vbios modding software.
-Those clocks are a little bit odd. Its completely intangible but a lot of people like to stick to the 1:2.5 ratio and to clocks that other cards have, like maybe 500/1250.
-You probably already know but its always worth mentioning, get some good cooling paste and repaste the GPU, clean out the fans and the vents, always leave clearance under your notebook and you may not have to downclock at all.

All that said its pretty cool what you've done here (no pun intended) +rep

 

Thanks for the info and advice.

I tried several downclocks at 0.9v but I can't do better than 450/1100/550 without stability issues like flickering screen and such, I guess my GPU isn't a good one for overclocks.
Anything other than 0.9v will give me black screen during heavy gameplay, no matter what my clock is, so I guess its not all about the clocks and its not about the temps cause I get around 50 for TSZ, 45 for CPU and 65-75 for the GPU during gameplay (I already cleaned the heatsinks and used ICD7 for CPU/NB/GPU).
My next guess is its a solder issue, I'll try to bake it in several days and hope for the best, I'll post here the results.

Anyway here is a link for the most stable bios for me with 450/1100/550 @ 0.9v

FX7811_9C.23.00_0.9v 450.1100.550.rar

 

I got some strange results with the 0.9V bios. It seems to cap my GPU to 2D desktop speeds (400,800,300). Even the nvidia control panel tools can't make it go above that. The 0.95V still lets me OC the GPU. I'll have to figure out if it actually changes the voltage or just reports 0.95V.

 

your 2D desktop should be capped at that clock since its the 3D performance clocks, it should go to the extra mode only when doing 3D at gaming and such.
I won't recommend using nvidia software for clock change, try using RivaTuner for that.

 

I'm still using .17. Is there any benefit to .23 to risk the flash?

 

If you are talking the STOCK bios difference then the .23 has the fix for the 1394 port so that when you hibernate you can still reboot without having to use the legacy drivers in windows 7. The other difference is that the GPU will idle at higher temps before kicking the fans on. If the solder issue effects your GPU this would prolongate the system life.

Now the 7811's came out well before nVidia stated they had fixed the solder issue. This could infer that the FIX was not fully in place with 78xx's before the boards were created. The 7805 and more recent boards were supposedly made about the time frame of the fix. This could mean they either are not subject or with better proccesses in place may not be as subject to the issue.

We can see 68xx's are having the issue cropping up. I think there has been even a dead 78xx or so come across the board, but not an allarming number of those. ALL systems will see some failure rate after time but since we know of a prior issue we are just more jumpy about it.............

 

Does this bios works on a 7811fx?

 

Yes, I made it specifically for the P-7811u FX, it shouldn't be flashed on any other model

 

There are two benefits, if you call them that.............

1.) .23 and above are made for Windows 7 as the 1394 port has to use legacy drivers without the bios upgrade to prevent a freeze when coming from hibernation.

2.) .23 and above also keep the GPU fan from kicking in at low temps. This may prolong any older cards from having the solder issue. Our systems were created at the borderline of nVidia switching over to the proper solder. Old P68xx were all efected by this and some of ours may be in the future as well.

If you notice the P79xx does not have this bios fix as the later nVidia cards do not suffer the solder issue. nVidia was aware of an issue at the time of our manufacture so hopefully we will have limited if no solder issues but again this is a guessing game right now and we are just waiting for the other shoe to drop.

On the bright side, if you cn say there is one, we are 2 years or more with some P78xx's and solder issues are few and far between. Is this a good sign as well?????????????????

 

so is there any difference between 7811 u fx and the standard 7811fx?

 

P7811u is the USA version like the P7906a is the Australian version etc. The letter designation is the system nationality designation. Mostly from what I can tell these are keyboard issues but there could be others as well.

The P7811 has the 512mb video card. the P7805 and some later models have the 1GB video card. I am not familiar enough but the vBios could be different between the 512MB and 1GB versions...............

 

I decided I'll try to bake the GPU and see if it has any effect on the black screen issue when using stock voltage.
I disassembled my laptop once again, sadly I wasn't careful enough when I removed the media panel and tore out the ZIF connector from the MoBo
after several hours of trying to glue the ribbon cable directly to the MoBo it works and I can power it on and off again yay!!!
Anyway, I used my plastic welding kit to bake the GPU at ~360F for several minutes, assembled the laptop back, it all worked but after flashing stock bios and running Dead Space after several minutes I got the black screen again ((
I guess either I didn't bake it at high enough temperature or either its not a solder issue

 

The supposed problem is the 2D-3D memory speed change. By underclocking the video card you are attempting to keep the card at 2D speed, avoiding the timing issue.

having older card and video memory your system may now be more prone to the cards issue. I would ask if you run battery for gaming does it black out as well? I think in battery you will never get to the last stage of GPU/Shader/Memory clock.

 

It seems that the problem has to do with the voltage of the GPU.
At 0.9 I won't have this issue at all, thats why I made the custom bios that only uses 0.9v.
At 1.11v I'll have the black screen issues even when downclocking to the performance mode clocks (400/1000/500 if I'm not mistaken).
On battery power the system won't let the GPU run on 1.11v, hence I won't get black screen on battery.
I'm gonna try and bake it a bit more at a bit higher temps and see if it has any effect.
Wish me luck

 

I just took it apart, baked it real good at around 410F, assembled it half way back to see if it works, well... the gateway still kicks!
Flashed stock bios and ran Dead Space again, still getting black screen
I'm pretty sure by now its not a GPU solder issue.

 

Right it does not run the higher voltage but more importantly no switching the 3D from 2D speeds. Have you tried keeping powwermizer off so that the GPU stays in high speed mode?

 

Yep, I tried powermizer off and still same deal, when I run 3D games at 1.11v I'll get the black screen and sound loop