Power Question

[Sanjurio]

So I put a new CPU fan in my Tower last night, it ended up requiring me to take apart the whole PC and take everything off of the Motherboard.
I got everything back together today, but the power switch on the tower doesn't work I have to turn it on from a button on the motherboard and after I booted it up it ran fine for about 5-10 minutes then it just randomly shut itself off completely without any warning or anything.
Anyone have any ideas about where/what I fucked up?

[Isiolia]

Is the fan not seated, causing it to overheat? That would be the first thing I'd check. Power switch not working might just be if you connected the switch to the wrong pins.

[Niya]

Yup, power button not working is probably because you connected the button to the wrong pins on the switch/LED header. Check your MB manual for what pin is for what button or LED and also watch the polarity.
About the random shutdown, use Coretemp/Speedfan to check your temperatures, or look inside your BIOS, most also display the current CPU temp.
If it's too high you'll probably have to take it apart again, check thermal paste, reseat the fan and put it back together. How did you distribute the thermal paste? Did you completely remove the old one (with alcohol/gas or something similar) before putting the new fan on?
The best way to distribute thermal paste that i know of is to add a drop of the paste to the center of the CPU heatspreader, roughly in the size of a pea. Then add the heatsink and press is down straight so the paste distributes evenly in all directions.