Help! No POST: Random boots, DVD drive acting weird Hi everyone! I'm having some serious issues on my sister's computer. Yesterday the computer was running fine, albeit the CPU was running rather hot (according to SpeedFan) and we decided to clean up today in order to make it run with more acceptable temperatures. But after cleaning the CPU fan and plugging the computer again, starting up would have either one of these two effects. 1) Computer boots fine, but soon (10-30sec after boot) shuts down. This happened not so often, and not at all now. 2) Computer starts up, all fans spin, but no beeps are heard (computer probably doesn't boot correctly). DVD drive beeps every once in a while, as if it was trying to read a faulty disc (no disc inserted though). Before the computer died completely (as it is now) the BIOS showed temperatures of: CPU around 40 degrees Celsius and System (I take it is something like the case's temperature) was around 30 degrees. I will post the computer specs later today when I retrieve the warranty papers from my sister's house. We have tried just about anything that could come into mind (and we had resources for): -Replacing the PSU (taking the one from my own computer) -Replacing the RAM (same as above) -Disconnecting all "unnecessary" stuff (optical and hard drives, network card, sound card, heck, I even took out the graphics card to check if it would help) The computer won't go into the POST stage, and when the display is connected, it just goes into power saving mode, whether the computer is running or not. I'm pretty sure somehow either the motherboard or the CPU is fried, but would like to hear from the forums before I take it to the shop where I bought the parts from and say, "Hey, the computer is dead, mind fixing it for me?" or something There might just be something small I have not taken into account, but seeing as I have worked on it for a few days already, I'm pretty sure I have covered everything that comes into mind. Therefore help is appreciated (as always). Thanks in advance.