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View Full Version : 6800LE to NU+


ATiMan
04-24-05, 02:52 PM
I have a 6800LE which has 8x1pp,4vp and i can unlock additional 8 pipes and 2 vp to go at 16x1,6vp. One quad seems defective(heavy artifacts) so i am at 12x1,6vp@400/900 using RivaTuner . Can i make a bios mod that will enable only the specific quads(i.e 0,2 and 3 enabled , 1 is the defective must be disabled). If i try the 6800nu bios it uses quad 1..
So is there a bios modification tool for unmasking disarable pixel quads?

ATiMan
04-24-05, 03:11 PM
On second thought, pixel pipes are locked on hardware level(using short jumpers or resistors) so i doubt bios has nothing to do with it.

Subtestube
04-24-05, 05:54 PM
Yes, there is a bios patch script included in Rivatuner to make the 'softmod' a 'firm-mod'. I suggest reading the FAQ.

Gentle
04-24-05, 10:54 PM
I thought the LE units are not the same as the rest of the 6800 series...

What is the chipset revision on that one? NV41 ?

Gentle

ATiMan
04-26-05, 04:37 AM
I thought the LE units are not the same as the rest of the 6800 series...

What is the chipset revision on that one? NV41 ?

Gentle

It is NV40 A1. I dont think there are major internal architecture differences on the pixel or vertex pipes if any at all between members of NV4x.

ATiMan
04-26-05, 06:11 AM
Ok i used the script in the NV40BIOSHwUnitsMaskEliminator directory of rivatuner to make a new bios file from the default bios. Then modify it with Nibitor2.1 to change core voltage and core/mem clocks and then reflash it with nvflash. Now 12x1,6vp@400/890 without the need for nvstrap driver. Cool!

Now is there a way to change the device id?(using nibitor or nvflash --guid didnt make any difference, still is recognized as 6800le within windows)

Kickus_assius
04-26-05, 01:40 PM
They all use the same drivers, so I wouldn't worry about the product it recognizes.

ATiMan
04-26-05, 02:03 PM
They all use the same drivers, so I wouldn't worry about the product it recognizes.
Well yes this is true. However when i changed the bios to that of a 6800(non ultra) i noticed a small variation in benchmarks(others increase, others decrease).
Took a 6800 non-ultra bios with 128MB(download from the web) then use rivatuner script to unmask specific units , then nibitor to change voltage to 1.3 and core/mem to 400/445(890DDR) ,nvflash to flash the now modified 6800 non-ultra bios and thats it, now i have a 6800+(12x1,6vp)(name it 'plus' cause has 1 more vertex pipe and higher clockrates than a non-ultra 6800).
Card is now recognized as Geforce 6800.
Perfomance: (Forceware 76.44)
3dmark05 scores about 4000(3982 to be more accurate)
3dmark03 scores about 9300(9287 accurate)

all that on an Athlon XP 1900+ without dual DDR.
Not bad for a 250E card.

ATiMan
04-26-05, 02:26 PM
Generally if one is interested on making his 6800LE to 6800NU flashing with a 6800NU bios is not enough. One should find which pixel and vertex pipes are in good shape using rivatuner. Then use rivatuner script and the 6800NU bios to unmask only the good shape units. The bios file that rivatuner script makes has to be loaded into Nibitor to change core/mem clocks(straightforward) and voltage( this maybe a little tricky cause Nibitor2.1 doesnt allow 1.3V on 6800NU bios file, so one changes the device id to 0042, save file and then reload the file with nibitor to have 1.3V enabled and changeback device id to 0041). Save the bios again, make a boot disk with nvflash and the bios file , reboot and at the prompt A:\nvflash <biosfilename> -4 -5 -6.

So with Rivatuner,Nibitor and NVflash you can make a 6800LE to 6800NU+(plus means that you usually end up with a card which is better than a 6800NU. Depends on the number of additional 'proper' vertex and pixel pipes.)

Subtestube
04-26-05, 05:26 PM
Just a wee note: I know if you look around you'll find people here repeating this ad infinitum, but beware of voltmodding. It, more than anything else, has the capacity to kill your lovely overclocked 6800. You may wish to consider dropping back to your stock voltage.

ATiMan
04-27-05, 02:02 AM
Just a wee note: I know if you look around you'll find people here repeating this ad infinitum, but beware of voltmodding. It, more than anything else, has the capacity to kill your lovely overclocked 6800. You may wish to consider dropping back to your stock voltage.
If i return to stock voltage cant go more than 350Mhz core.1.1V to 1.3V is about 18% difference. It is out of the standard +-10% deviation (which most electronic equipment can handle) but since cooling looks good(core temperature never above 75C), no reason to worry.
Besides 6800GT have the exact same core with 1.3V(stock voltage) and 16pipes@350, mine card is with 12pipes@400 and 1.3V why should i worry. I dont think that a 6800GT core can take more heat or current than mine, the difference is that this 4 extra pixel pipes were made fine and can work at 350Mhz.

jimmor
04-28-05, 06:43 AM
If i return to stock voltage cant go more than 350Mhz core.1.1V to 1.3V is about 18% difference. It is out of the standard +-10% deviation (which most electronic equipment can handle) but since cooling looks good(core temperature never above 75C), no reason to worry.
Besides 6800GT have the exact same core with 1.3V(stock voltage) and 16pipes@350, mine card is with 12pipes@400 and 1.3V why should i worry. I dont think that a 6800GT core can take more heat or current than mine, the difference is that this 4 extra pixel pipes were made fine and can work at 350Mhz.

6800LE or NU bioses can be set anywhere between 1.1 and 1.4v !

The Voltage is determined by the GPU Volts Lookup Table iaw the following rules,

6E00 sets 1.1v
7801 sets 1.2v
8202 sets 1.3v
8C03 sets 1.4v

So if you want 3D at 1.4v, then just make sure that last position of lookup table is "8C03".

Or since many 6800LE and NU manufacturers have already set their bioses with a FALSE 1.4v option of either "8C01" or "8C02", it is probably easier to just change that to "8C03"