Some months ago I build a custom HTPC with an ASUS motherboard (model P5N7A-VM). I never had any problem with it until I hooked it up to my TV using a resolution of 1080P. While playing Eve-Online, it started to crash and reboot after playing only 15 minutes!
After investigating I found out that the chipset (with on-board graphics) was overheating badly and causing the reboot when it reached about 90°C. That’s really hot! For comparison, the CPU was stable at 40°C idling and climbed to about 47°C while working at 100%. ASUS did a poor job on designing the heat dissipation apparatus on that particular motherboard. I’m currently looking on workarounds. Adding extra fans will be complicated because it is installed in a small case, an Antec model NSK 1380. Water cooled solutions are troublesome to installed and messy. I already have a PCI slot fan that was bundled with the case. I’m thinking about adding a heat pipe but I read on a forum that it will only help reduce the heat about 5 to 10°. I also tried using a separate graphic card while disabling the integrated GPU. The chipset was still overheating. If you have a better idea please post a comment!
Update : I’ve opened my case and simply added a 40mm fan directly over the chipset heatsink. Now, temperature top at ~65°C while the CPU and GPU are fully loaded! A 25° drop! Not bad for a little fan. I’ve also upgraded to a dual-GPU (SLI) solution and now I really can enjoy gaming and it only raised the temperature ~5°C. The best part is that it’s now a rock solid system that doesn’t reboot by itself.