windows vista turn on/ crash problem

[milkncheese]

hello, recently, my computer that i have owned for about 3 years has been acting weird. sometimes, i cannot get the pc to turn on right. when i press the power button, all i get is the light it shows on the power button.(not flashing) .. i also get a BLACK screen, and on top of that, a loud fan noise. i checked my computer for spyware using the program spyware doctor. it removed all harmful programs but hours later, the computer crashed on its own. now i might know what is causing this but im not sure....sometimes when i'm playing pc games, it just freezes up so there is nothing i can do but hold the power button. i know i am not suppose to but i don't have a choice. can that be the problem? please help me guys, i need you help.

[patio]

Overheating would be my first guess...
Remove a side panel and determine which is the offending fan...
If it's the PSU fan get a new PSU.

[milkncheese]

i dont believe it is overheating. i cleaned all the fans out a while ago.. that was my recent problem. but now, when i restart the computer, i get a black screen. so im pretty sure it isn't overheating.

[BC_Programmer]

i get a black screen. so im pretty sure it isn't overheating.

Err... OK... and what would happen if it was overheating?

[patio]

and on top of that, a loud fan noise.

You have a failing fan in there somewhere...

[milkncheese]

if it was crashing, it would just shut down. and when it turns on, it wouldnt have a black screen...right? )= the only way i can get it to turn on is when i play with all the power outlets until it works.

[patio]

You have a failing fan in there somewhere...