Stability was excellent running the burn-in tests and every day use. I used the motherboard with a 7800GTX from XFX in single mode for days without problems. One oddity, was trying two XFX 7800GTXs on this board. The cards were not stable at all with two cards in SLI mode. NVIDIA's driver correctly identified the cards, and correctly set it into SLI mode, but running any benchmark would cause the board to freeze and restart the computer.
With our normal 6800GT card in place, and either of the 7800GTX cards, stability was excellent. Strangely, I tried to SLI the XFX cards on a Gigabyte board, with the same result. NVIDIA's partners may have to release a BIOS update, to enable stable SLI function with the nForce4 for Intel SLI motherboards and the newest 7800GTX cards. On a AMD SLI platform, I had little difficulty using SLI on the 7800GTXs.
Overclocking on the Asus P5ND2-SLI board was limited by the CPU (3.4GHz Extreme Edition) we use for testing. The board successfully overclocked to 3.57 GHz, but the CPU temperature was a measly 40C. Every board I've tested this CPU on barely overclocks at all, meaning the 3.4GHz EE is the limiting factor most of the time, not the motherboard. PC Probe is Asus's system information utility. From here you can get information like what every device on the computer is, hdd usage, memory usage, CPU usage and other useful information. AI Booster is ASUS's over clocking utility.It uses a temperature gauge and voltage reading to determine what over clock the motherboard is best suited for. You can set the CPU overclock to 115% of rated speed with AI Booster. NOS stands for No-Delay Overclock.
