Hi All,

Recently i removed the HeatSink and cooling fab to clean all the crap off that had built up over the years.Left the cpu in plcae but cleaned off all the old thermal paste with an alcohol based cleaner.Replaced all the cleaned items.Now pc wont switch on.There is a small green light visible on the motherboard when it is plugged into the wall socket.
Any help and ADVICE will be appreciatedBreaking the seal is never a good idea unless you intend to replace the CPU.

You didn't use alcohol on the CPU, did you? Not a good idea.

Dumb question: Did you REAPPLY more paste?I did reapply a silicone based thermal paste to the cpu prior to replacing the Heatsink and fanDouble-check to SEE if the heatsink is seated fully...
Double check all PSU connections.
Does the CPU fan come on ? ?

Thermal Compound Instructions

Using too much is as bad as using not enough.Hi Patio,

Thermal paste was spread evenly over the cpu COVERING cpu to just short of the edges to accomadate any spreading of paste.Heat sink is properly seated.All connections clean and secureDoes the CPU fan come on ? ?Sorry Patio

WILL PAY ATTENTION in future.

Sorry no CPU fan does not come onThen all the connections are not correct and/or the PSU has gone south.
Can you borrow another one of the same or greater wattage and swap it in there to see if it's the culprit ? ?
The CPU fan connector should only go in one way...however if you forced it it may be in backward. Try reversing it as well.Hi Patio,

Here`s the thing................. ok will try to get another PSU.
After checking what you told me i got the @#$%^ with it and left it plugged into a wall socket and closed it up.About an hour or so later i walked past the thing and noticed that it had started up.Fan was RUNNING side extractor fan was running.Will unplug it and set it up properly and see what happens.This is so wierd.Can you think of why it would just start up after so long without anyone trying to switch it on or off