My C2D E6600 is running extremely high, at around 75-80 degrees, I know what the problem is and I am getting it sorted out to what it should be at (30's for my build) on Tuesday / Wednesday.
Would it be alright to use my computer before then, or will it damage my CPU / even destroy it?
This is idle temps BTW.

Thanks for that, but anyway, could you answer my original question? =]

I would turn it off and read a book or something until it's sorted out. I don't know if it will destroy the CPU completely, probably not, but it will reduce its lifetime. It may also reduce the temperature at which it starts shutting off in the future. Play it safe...

What do you mean by "reduce the temperature at which it starts shutting off in the future?"
I'm guessing you mean that once I've sorted it out, the temperatures will be lower once it's turned off in the future? :S

The CPU has a safety feature - if it reaches a certain temperature it starts reducing the frequency to protect itself. The temperature where this happens depends on the model and stepping.

Let's say it reaches 72 degrees and then it drops from 2.4 GHz to 1.6 GHz (all numbers invented, but you get the idea). If this happens often, it may start doing it at 70 degrees, then at 65, etc. I've only read about it in forums and can't guarantee it's true. Still, it's probably safer to avoid testing the theory on your own CPU.

The last guy i helped that had just built his pc and it was running way hot had FORGOTTEN to remove the clear plastic between the CPU and the heatsink thermal paste....,

Do you remember taking the clear plastic off??? If you don't, shut that thing down and do it right before it fries...

He did say he knew what the problem was. By the way, what is it???

Heatsink clips not working properly, so not enough downward pressure onto the CPU, causing it to overheat.
However, I've ordered a new heatsink to work out the problem, well hopefully it will.

I hate those four pinned heatsink types! Would rather have a backplate so I can apply some greater pressure = better heat transfer.

if it really idles that high, then you best not use it.

Well, the really weird thing is that it must have been running high for such a long time, maybe weeks or even months, as randomly one day I wanted to check my temperatures and found out that they were running this high..
I never knew to check or anything before. +_+

So what cooler did you get???

I have a Thermalright ultra 120 extreme and it's really REALLY GOOD!!

I've OC'd my system from 2.4 - 3.7 and it sometimes cracks 50-52 under load... but rarely.. most of the time it sits in the 27-30 range depending on ambient temps... it was 80 here in the house the other day and it reached a whopping 31 idle and 54 under load

I got myself a beautiful Thermalright Ultra-120, but not the extreme!
Is it really that good? What 120mm fan did you put onto yours and does it just plug into any old chassis fan socket?

Theres only a 1-3 degree difference between the Ultra-120 and the extreme, you still have a bada$$ cooler.

75f sure 80c no!

power off and read a book. then play to your hearts content with the new HSF