Hello,

I purchased a new power supply today and swapped out the factory installed unit in my Dell XPS whatever. The new supply is 550 watt, whereas the old one was something like 340. In any case, the computer will turn on briefly (about 1 - 2 seconds) and then everything shuts down. This is very repeatable.

The motherboard is receiving power, because the indicator LED is lit. I have also tried hooking up the previous power supply to the motherboard (both 24 pin main and 4 pin supplemently) and hard drives to see if it would make any difference and the result is the same: the computer turns on for 1-2 seconds and then powers down, the motherboard LED lit the whole time.

In the process of changing out the power supply, I was forced to remove the heat sink and this, as far as I know, is the only conceivable spot where something could have gone wrong. Before replacing it, I removed the previous conductive goop (from both processor and heat sink) and reapplied a fresh, even layer to the processor, taking care to not wiggle the heat sink after it was firmly nestled atop the processor once again.

Please, if you have any idea what may be wrong, let me know.


Sincere thanks,

Steve

I noticed in your question you referred to the heat sink as "conductive", it is nonconductive. If you used a conductive substance that could be a real problem.