There is a nifty little trick that can enable SLI on a non-SLI motherboard by simply flashing the BIOS.
There's nothing cooler than a little cheat, a work-around that opens up a whole new world in squeezing out all the performance juices a PC can generate. Granted, sometimes a little tweak here and a little tweak there can generate the opposite effect, rendering the machine literally "bricked" in a sense that the damage is mostly irreversible. However, BIOS modifications are nothing to sneeze at, and require a bit more knowledge to manipulate than average users may think. With that said, forcing SLI on a non-SLI motherboard is not something Tom's will officially endorse, and may very well void the motherboard's warranty if the process goes haywire.
Apparently, Tweaktown has stumbled upon an article in Taiwanese magazine PC Home Advance that explains how to enable SLI support on a motherboard without Nvidia's prized SLI certification. According to Nvidia, motherboard manufacturers using Intel's X58 chipset must pay for the company's official certification if they want to enable SLI support in Nvidia's ForceWare drivers. But what if the motherboard can offer SLI by flashing it with another certified BIOS? Would that be cheating Nvidia? Would that even work?
For Gigabyte's EX58-UD4, the method does work according to the PC Home Advance article. The magazine managed to flash the motherboard with the latest F6 Gigabyte EX58-UD4P (note the "P") Nvidia SLI-certified BIOS and actually enable SLI on the cheaper EX58-UD4 model. Ironically, the EX58-UD4 offers CrossFire multi-GPU setups right out of the box, so by flashing the BIOS, the board thus supports both CrossFire and SLI. Coolness.
In order to get the SLI mode set up, users must grab a copy of Spiflash.exe, a DOS-based flashing program, as other flashing programs such as QFlash and @BIOS will not work. Next, reboot the PC using a DOS boot disk (or USB thumb drive for that matter) and enter the DOS command prompt. From there, users simply need to enter the command "SPIFLASH EX58UD4P.F6" and voila! The BIOS flash update will commence. Once that completes, users simply reboot the PC back into Windows; SLI support should now be readily available.
While the process sounds easy, enabling SLI on a non-SLI motherboard is not guaranteed to work, and may even render it useless. However, it will be interesting to see if consumers can get the SLI up and running, and if Gigabyte and/or Nvidia will release any kind of statement in regards to this SLI "cheat."