|How To Overclock the NVIDIA GeForce 8800 Series|
|Articles - Featured Guides|
|Written by Olin Coles|
|Sunday, 18 February 2007|
Page 2 of 3
Programming the BIOS
EDITORS NOTE: This instructional article is available as an archived reference. The updated replacement is titled: Overclocking the NVIDIA GeForce Video Card and is now available. The new article will receive periodic updates and become part of a larger series focused at optimizing, tuning, and overclocking the computer system.
Welcome to page two of my guide. On the first page, I discovered the maximum potential of my video card. Since I have already tested my overclocking results with both artificial loading and real-world usage, it is now safe enough for me to modify the video card BIOS file with my new overclocked settings and make the FOXCONN 8800 GTS operate with enhanced performance without additional software. This will make the card identical to factory overclocked versions.
Unfortunately, part of this process requires that the system boot into MS-DOS with a 3.5" floppy disk drive, which I normally don't have installed in my computer because it is considered an obsolete legacy piece of hardware. The USB flash drive and recordable optical drives have proven themselves to be very good solutions in terms of suitable replacements, so it may become a difficult task locating a 3.5" floppy disk drive any further into the future. For the remainder of this project, a bootable USB flash drive or a properly created bootable CD/DVD could have been substituted, but I choose to avoid reinventing the wheel and retained the use of a spare floppy disk drive to complete this project.
To begin the (simple) process of creating a custom BIOS file, I utilized the free NiBiTor program to save a copy of my original BIOS. There are two steps for this process:
Save a backup
I should only continue after creating a backup of the original video BIOS, since this file will allow the opportunity to return my settings back the factory defaults if it is every required. It is highly recommended that this backup BIOS file be copied and renamed so there will be both a working copy and the original backup file available. I named the original BIOS file "BACKUP.ROM", and then created a copy of it which I named "8800GTS2.ROM".
Additionally, the good people at MVKTech who helped build NiBiTor have also created a BIOS repository, where they kindly request that you upload your original BIOS file. This could be useful later if you happen to misplace your backup, or want to see what other manufacturers have done to tweak their BIOS configurations.
Up to this point, I have saved my modified video BIOS "8800GTS2.ROM" onto one floppy disk. I will then save the nvFlash program (which is available for free download) onto this same floppy disk. On a second floppy disk I will use Windows XP to format and create an MS-DOS startup disk. It is may not required to split the project files and nvFlash from the MS-DOS startup disk because of file sizes and available space, but this is a safe practice which also decreases the chance for possible media problems.
Now that a backup of the video BIOS has been copied and stored for safe keeping, the next step for reading the working file and making changes begins with: File → Open BIOS (Choose the renamed copy "8800GTS2.ROM" of the video BIOS here).
Once again, the novice could become very concerned about the many tabs and options available in NiBiTor, but for my purposes I will only use the Clockrates tab to change the values for 3D speeds.
Using the values discovered and tested to be stable in my previous steps, I apply these values into the appropriate 3D fields, replacing the original values. Once I have typed in the new Core and Memory values, I saved this modified video BIOS file by choosing: File → Save BIOS (save this modified file onto a formatted floppy disk and name the file something simple with less then eight characters such as "8800GTS2.ROM").
Flash the BIOS with nvFlash v5.40Now that I have prepared the new modified video BIOS file and saved it to a floppy disk, I am ready to make my video card operate as if it came from the factory with my new settings. I will now flash my working copy of the modified video BIOS "8800GTS2.ROM" onto the FOXCONN 8800 GTS using nvFlash.
Flash the new BIOS
Flashing a video BIOS is a very simple process; yet extra care and precaution must be taken or the hardware being flashed may be rendered non-operational. I have taken steps to ensure my computer systems stability will not be compromised by removing any system component overclocking (CPU, RAM, bus speeds), and have placed my system on a 1500VA backup battery UPS. With stability ensured, I am ready to move forward and flash the video BIOS.
The video card BIOS is flashed by:
That's it! The hard part is done. Once the system reboots after the successful BIOS flash, the video card is programmed with the new enhanced performance settings. But am I finished?