So i had this older computer and i took the fan off and put it back on but i thought i had it on correctly and whenever i turn on my computer windows starts up and then shuts off. is it my fan or my processor or do i need more thermal paste on my cpu?
take of the cpu cooler again and whip off all the old thermal paste so the metal is nice and shiny.
then apply some new paste. make sure you don't use too much and make sure that the cooler is secured properly.
hmm. it might be possible that there is a bad connection or some malfunction somewhere on the Mobo.
it could also be the RAM. i'll say the possibilities for a problem with the RAM is greater then a motherboard problem.
you could try out memtest to see if your RAM a working properly.
have you checked it it's an overheating problem?
you should quickly be able to see if it is in the BIOS.