Please read my other thread regarding the asus motherboard, i took out the other motherboard as i thought it was dead, but got a new motherboard as i had already had one on order before i thought the other had blown, just built the other motherboard up but seems to be doing exactly the same as the old one, won't switch on.

You tried a different PSU?

No, that is the only thing i've not tried, but would it still be the PSU if the lights on the motherboard light up when i plug the power in?.

yes

If you over-clock your CPU you run the very real chance of it overheating. Contrary to popular myth, there is nothing in a computer that will enjoy running over 35 degrees C and many processors run at closer to 50 most of the time, which for any chip is asking a lot. the same applies to your PSU and yes parts of it may still run the low current components on the board but it may well have cooked the main regulators and be incapable of giving anything enough current to actually run.
When you select a PSU for a computer, I strongly suggest you over-rate it by at least 100 watts based on the total requirement from everything on the system. This calculator is pretty good at keeping you out of trouble in that area. Under-rated PSUs are the main cause of most failures in stock equipment,.. trust me, I've spent 35 years fixing them.
http://www.journeysystems.com/support/calculator/
You have probably blown the CPU as well, with heat and probable voltage spikes when the PSU fried.
If you really want a faster machine, do not over-clock the CPU, buy an serious upgrade, it works out a heck of a lot cheaper than replacing cooked ones that the manufacturers will always tell you "over-clock at your own risk",.. and for very good reason!

That last 'anonymous' post was mine, I just forgot to sign in first. Just as a background to my wee rant. I've been in computers since they were the size of a few decent fridge-freezers and took enough power to run a small town. Odd thing is, the mistakes made by a software genius saying they can get more out hasn't changed in all this time. They blow a lot of stuff to kingdom come, always have.
If we, the guys and gals who designed the hardware say it has a limit, we did actually test it and the limit is exactly where we said it was. If you must push the envelope, expect something pretty crucial to fail without much warning!
There is one other crucial motto we suggest you live by. RTFM.

In reply to a post by pbsolo:

Just as a background to my wee rant. I've been in computers since they were the size of a few decent fridge-freezers and took enough power to run a small town. Odd thing is, the mistakes made by a software genius saying they can get more out hasn't changed in all this time. They blow a lot of stuff to kingdom come, always have.
If we, the guys and gals who designed the hardware say it has a limit, we did actually test it and the limit is exactly where we said it was. If you must push the envelope, expect something pretty crucial to fail without much warning!
There is one other crucial motto we suggest you live by. RTFM.

Then your post is frightening for how long you've been doing it.