Follow along with the video below to see how to install our site as a web app on your home screen.
Note: This feature may not be available in some browsers.
Optimummind said:*DISCLAIMER: This flash will work on all brands of the 6800 GT series cards. In this guide, I'm using my BFG brand 6800GT. DO THIS AT YOUR OWN RISK. Although the BIOS procedure is relatively simple and quick, not following the directions carefully may result in frying your card if you don't have adequate cooling.
------------------------------------------------------------------------------------------------
Here is a quick guide to what I did to increase the stability and overclockability of my retail BFG 6800GT OC card. (BTW, this flash guide pertains to other GT cards as well--not just the BFG brand.)
Before the flash, my card could go up 420/1150MHz. At those speeds, all games and benchmarks were stable (Far Cry, 3DMark03, etc). However, it wasn't stable in one game which was very annoying--Warcraft 3. The single player mode would run fine but my BNET connection would keep getting disconnected after 30 minutes or after an hour.
After eliminating the issues of heat or inadequate PSU, I concluded that the issue must've been with the voltage being supplied to the core. My research online revealed that the GT cards receive a voltage between 1.3 V to 1.33 V. The Ultras, on the other hand, receive v1.4 V.
So, I searched for a BIOS rom that would increase the voltage to my card to 1.4 V yet not mess with any core and memory speeds and timings. After I found such a BIOS, I flashed my card with it. As promised, the BIOS didn't alter any core and memory speeds (checked with Rivatuner and Coolbits 2).
Well, how do I know the voltage changed? Although I don't have the physical tools to measure the voltage running across the board, I did notice the improved stability of my card after this flash. My OC has increased to 440MHZ stable and War3 doesn't disconnect me anymore.
Here are the steps I used:
(1) Download the nvFlash utility. I used version v4.42.
(2) DL'ed the specially modified Leadtek GeForce 6800 Ultra with voltage of 1.4 and no changes to core and memory speeds. You can find it here.
EDIT: Instead of using the Leadtek BIOS, I am now making my own custom BIOS files based on my BFG GT's rom. Here is the link to a page where all my BIOS creations are stored (about 23 dif kinds). Thx goes to [H]ard member Zok for hosting these!!
The BIOS were customized using HexWorkshop and NVCHK.
Remember to have good cooling in order to flash to this BIOS.
(3) I put the above 2 files in the same directory of my choice.
(4) Start-->Run-->cmd
(5) Browse to the folder that contains the flash tool and the BIOS rom.
(6) Typed this command in to backup my card's original BIOS:
nvflash442 -b mybios.rom
(The "mybios.rom" portion is arbitrary. You can name the BIOS to whatever you want.)
(7) With my BIOS backed up, I proceeded to flash to the new Ultra BIOS. I typed:
nvflash442 -p -u -2 ultra.rom
(The "ultra.rom" portion of the code is also arbitrary. Whatever the Ultra BIOS name happens to be, you'll be typing in that name.)
(8) The flash process took a while for me--like 1 minute. When I saw the flash successful confirmation message, I rebooted my computer.
(9) Once I reached the Desktop, WinXP detected my "new" GeForce 6800 Ultra. It asked for drivers so I installed the newest official one--the 61.77.
EDIT: If you flashed your card using one of my modified BFG GT BIOS, your WinXP won't detect the "new" Ultra. nVIDIA driver control panel will say it's a BFG 6800 GT card.
(10) Installed Coolbits 2 and verified that the clock speeds weren't altered. I slowly OC'ed my card until I reached a satisfactory level.
EDIT: The core and memory speed will be different depending on which BIOS file you used to flash your card with.
That's it! It was safe, quick, and too easy to be true.
Just like how I used to flash my 9800 Pro that I sold through this forum, the process is simple and effective as long as you pay careful attention to the details and directions.
Just make sure that you have a sufficient cooling system in place to buffer the extra heat your card will generate after the voltage increase. My idle temp went up from 51 C to 53 C.
EDIT: Now that I have a DangerDen NV-68 block on the GT on its own water loop, my idle temp is 51 C for the core and 32 C for the ambient idle (card is running at 430/1150). For more details, you can check my DD NV-68 project log. .
Good luck and have fun and be careful about your temps! Once again, thx to member Zok for hosting all those files!
-Optimummind
460cidpower said:Has anyone ever tried that with a plain 6800? (plain 6800 to GT) If a modifide bios was used? i.e. the core/mem speeds the same as stock. Would the lack of the extra 128 MB of ram mess it up? Because I know that Asus makes a 128MB GT card. So if somone modified it's BIOS to stock 6800 speeds, it may be possbile.
I(illa Bee said:why would you modify the 128mb ASUS GT BIOS to 6800nu speed then flahs it? whats the point?
the 6800nu is a 12 pip card, the GT is a 16pipe card, its not exactly like the 5900nus and 5900U...
There other diffrence other than clock...so its hard to say, i thought i read some peopel getting the 12 pip NUs to full 16pipe GTs...
MeTaSpARKs said:Waiting.. waiting... waiting...
460cidpower said:Becasue I had heard that SOME of the 12 pipe nu s can be modded to 16 pipes using software. So one could assume that a bios flash from a GT(modded to NU speeds) could make that possible.
Butter Bandit said:Increasing my voltage to 1.1/1.4/1.5 caused my card to crash at low speeds (temp never exceeded 55C, it is watercooled).
It does something strange everytime it crashes too, the colors on the screen turn all funky, and then digitize really badly, and then it just reboots. I'm used to my video cards simply locking up, or instantly rebooting upon a bad overclock, anyone else seeing this same thing, or did I just damage my hardware.
jak-c said:ok ok. Im very new to overclocking (what am i doing here u ask) But ive got a MESH dekstop turning up on Monday with a 6800GT in it. It twas supposed to be an ultra but they were outta stock and i was impatient and went for a load of extra goodies instead.
Aneeeeehow. I dont have a water-cooling set up ,just the regular standard fans, but i wanna OC the thing. Ive looked at all the advice on this Thread but theres so much its hard to know which one to take. Someone guide me through this, I just want some extra power/speed. Lamens terms please. Which drivers should I get or BIOS files? Help.
jak-c said:ok ok. Im very new to overclocking (what am i doing here u ask) But ive got a MESH dekstop turning up on Monday with a 6800GT in it. It twas supposed to be an ultra but they were outta stock and i was impatient and went for a load of extra goodies instead.
Aneeeeehow. I dont have a water-cooling set up ,just the regular standard fans, but i wanna OC the thing. Ive looked at all the advice on this Thread but theres so much its hard to know which one to take. Someone guide me through this, I just want some extra power/speed. Lamens terms please. Which drivers should I get or BIOS files? Help.