Computer Start Up Problems

Hi

The problem is when i start my computer from about a day of not being used, the power light comes on like it usually does but then the monitor doesnt display anything and the CPU fan goes mad! Revving at its maximum, It will stay like this until i turn it off.

But when i turn it back on again after about a minute it loads the normal screen that shows what cpu is installed and that is how far it will go and it freezes again. (at this point the cpu fan is normal)

Occasionally...
It will load up the same screen but it gets to installed hard drives/dcd drives and then stops again

Then...
After a couple of attempts at turning it off and on again it will work completely fine! It turns on like usual and i can log on and do all the stuff that i can, but it doesnt freeze again... ever! :S

Someone please help me! Whats wrong with it?

Is the computer you're referring to the one under your 'system specs' ?
How old is it? It sounds to me that your PSU is defective.

the psu is under 1 year old and is 750 watts and yes it is

The power supply (PSU) is under 1 year or is it the computer?

the PSU is, various parts of the computer are at different ages because its custom built

Thanks for clearing that up.
I still have my mind stuck on the power supply though.
Are you sure it is strong enough?

well i think it should be but do you think it could be anything else? it all just started the other day it has never done it before :S

A power supply can go bad in minutes. It doesn't tkae long at all.
Is your computer plugged into a surge protectoer of some kind?
You'd be amazed at how many power surges that are out there so small that we don't even notice...
But believe me, the computer notices...

yeah its plugged into a surge protector

i took it out of its case this morning and laid it onto my desk and turned it on and now it seems to be working fine :S this is really confusing me now