Bios Vmod for 6800

Samuknow · #1 (**permalink**) 18th March, 2006, 06:58 PM

I did this for my Evga 5900 card and it would run all day at 5950 Ultra speeds. I did have it watercooled though. I was planning on flashing my Winfast (leadtek) 6800 to 1.4 to get a better oc out of it. I just ran nvflash to save the bios and the default is 1.2 V. I am running 16 x 6 with no artifacs and the card OC'd easily to 375/800. I think it can do better with a little persuation. I am using nibitor to view and mod the bios. The only thing I want to change for now is the volts.

Has anyone else done this? How were your results?

Samuknow · #2 (**permalink**) 19th March, 2006, 07:36 AM

No one has an answer????

Samuknow · #3 (**permalink**) 22nd March, 2006, 07:00 PM

Well despite the overwhelming feedback. I did the flash. I did manage a better OC with minimal temp increase. The bios tool will let me set the 3d vcore to 1.5V. I will let it run for a while and try a little more. O yea it is now at 405/855 with 16x6 unlocked and I hit under 12000 on 03. I can't remember what it ran stock.....Maybe I will set it back to get a comparison....

What is the highest anyone has gotten their 6800 non gt/ultra?

madcatmk3 · #4 (**permalink**) 22nd March, 2006, 07:50 PM

sorry for the no feedback I have no experiance in the matter, good job on the oc though.

Toastmaster · #5 (**permalink**) 22nd March, 2006, 08:41 PM

This isn't exactly the feedback you're looking for, but I voltmodded my 7800gt just like this with nvflash and nibitor the other day. I had no problems with the flash and I've now got it running at 476/1206 (well over stock speeds of most lower-end GTX's). So far 100% stable with maybe 1 or 2 degrees temp increase from my stock speeds. (36-38 idle, 66 peak)
Good luck with your O/C, I read somewhere that 6800s are good overclockers, but I've never had one so I wouldn't know for sure.

dsio · #6 (**permalink**) 22nd March, 2006, 10:26 PM

OK, I'm running my 6800GT with an ultra-extreme edition bios, which gives an extra .1 core and .05 DDR. Brings mine up to 1.44V measured with an accurate multimeter.

After that I used the pencil mod on the regulator resistor to bring it up closer to 1.66, which its very stable at and still rather cool.

The clockspeed I'm running is 455Mhz core 1.2Ghz RAM, with 1.25Ghz RAM also stable.

In 3Dmark05 I'm pulling 6400 right now with good image quality drivers, and 2950 in 3DMark06. I don't use 3DMark03, as it really isn't a very good benchmark to use.

If you want to try the resistor mod, I can post some pics of how to do it. All it takes is a lead pencil, a multimeter, and a few seconds. It can be applied to both Vcore and VDDR

Samuknow · #7 (**permalink**) 23rd March, 2006, 05:26 AM

Quote:

Originally Posted by dsio

OK, I'm running my 6800GT with an ultra-extreme edition bios, which gives an extra .1 core and .05 DDR. Brings mine up to 1.44V measured with an accurate multimeter.

After that I used the pencil mod on the regulator resistor to bring it up closer to 1.66, which its very stable at and still rather cool.

The clockspeed I'm running is 455Mhz core 1.2Ghz RAM, with 1.25Ghz RAM also stable.

In 3Dmark05 I'm pulling 6400 right now with good image quality drivers, and 2950 in 3DMark06. I don't use 3DMark03, as it really isn't a very good benchmark to use.

If you want to try the resistor mod, I can post some pics of how to do it. All it takes is a lead pencil, a multimeter, and a few seconds. It can be applied to both Vcore and VDDR

I would love to see that mod.....I did think about flashing to a GT or better bios. I have not found one for a leadtek card though....

dsio · #8 (**permalink**) 23rd March, 2006, 05:41 AM

Here in the first picture is the resistor that you pencil mod. At stock it should be 8K Ohms. Using a pencil across the top of it (the exposed terminals of the resistor) drop it to, but no lower than 7.4K Ohms measured.

A little bit goes a long way, so keep that in mind and use the pencil sparingly.

To measure your real voltage, check from the point shown in the second picture. Do check it before you volt mod, to see exactly what your BIOS tinkering has done and where your card is at.

Ill find the DDR mod later.

This one is only Vcore.

chrisbard · #9 (**permalink**) 23rd March, 2006, 06:01 AM

Is it possible that this mod will also work for my 6800 LE ? My max core clock is now 330

Thanks for any answer !

dsio · #10 (**permalink**) 23rd March, 2006, 06:23 AM

It should do. NV40 is NV40. They vary slightly, but are all the same rough design and use the same voltage regulation design. Be carefull when you do it, thats all I ask.

Samuknow · #11 (**permalink**) 23rd March, 2006, 08:08 PM

Sweet. I will try thins when I get a little time. Been burning the candle both ends and the middle the last couple of days.

Look forward to the DDR mod.....

Thanks

chrisbard · #12 (**permalink**) 29th March, 2006, 08:55 AM

Quote:

Originally Posted by dsio

Here in the first picture is the resistor that you pencil mod. At stock it should be 8K Ohms. Using a pencil across the top of it (the exposed terminals of the resistor) drop it to, but no lower than 7.4K Ohms measured.

A little bit goes a long way, so keep that in mind and use the pencil sparingly.

To measure your real voltage, check from the point shown in the second picture. Do check it before you volt mod, to see exactly what your BIOS tinkering has done and where your card is at.

Ill find the DDR mod later.

This one is only Vcore.

OK I am ready now to do this and I have all the instruments, couple more questions before trying it though:

1. Doing the pencil thing would help me raise the core freq if nothing else is done?
2. If I also must reflash the card from where do I get the bios
3. What bios should I get for my Palit Daytona 6800 LE 12/6 ?
4. What is the name of the program that is used for flashing?

Thanks a lot !

dsio · #13 (**permalink**) 29th March, 2006, 09:11 AM

Do NOT flash the BIOS. It is not needed, and can cause more problems than its worth. Just do the pencil mod, and make sure you use an accurately calibrated multimeter to measure the resistance as you change it, and the initial and final Vcore (this measurement has to be made while the card is under full stress rendering 3D. for the love of god, dont slip and join some contacts while the card is in use. There are many amps in play here.)

chrisbard · #14 (**permalink**) 29th March, 2006, 09:28 AM

OK Wish me luck. Since I have no other card around at the moment if something goes terribly wrong see you all tommorow

chrisbard · #15 (**permalink**) 29th March, 2006, 09:59 AM

OK guys bad news:

1. I am a moron and could not find this chip (could be under front cooler?)
2. The chip isn't here because of diferent card design???
3 I am very upset, do you guys have any ideea?
4. My camera isn't home so I did take some pics with a crap camera

Samuknow · #16 (**permalink**) 29th March, 2006, 05:34 PM

I did flash mine to 1.5v and it is screaming....I still have not topped it out yet...

I used nvflash to save the original bios and then modded it with nibitor.

Worked great....

z3speed4me · #17 (**permalink**) 4th April, 2006, 10:46 PM

i loaded the bios...where do i SAVE it....i feel like an idiot right now, like where is the default bios saved that i can like save over it?

Samuknow · #18 (**permalink**) 5th April, 2006, 05:43 AM

You save it back to the floppy you boot from. Then copy to your HDD in the same folder you DL nibitor to. Then open up nibitor and edit the bios and "save as" vmod.rom. Copy it back to the floppy. Boot to the floppy then flash with the modofied rom. I would try 1.4 first for a day or so to make sure you have no ill effects. Then if all is well mod the vmod.rom file to go to 1.5.....

Good luck