SLI 2x Asus GeForce 7800 GTX Extreme, Continued
The Coolbits registry hack unlocks the frequency selection dialog in the NVIDIA reference drivers. Once again, beware that the manufacturer will not cover any damage to the hardware resulting from overclocking-related overheating. In our test, the driver's automatic detection routine determined a maximum clock speed of 477/1288 MHz for both cards running in parallel. As a reminder, the stock clock speeds were 430/1200 MHz.
When overclocked, the SLI setup's noise level increased to 43.5dB(A). In operation, the dual-setup is about 4dB(A) louder than its single-card counterpart. The temperature, on the other hand, turned out to be lower in our tests, ranging between 52 and 73 degrees Celsius (2D/3D) both at stock speeds and when overclocked.