I had a computer repair job similar to this the other day.
The computer would work fine and then switch off randomly (may last 2 mins, may last hours) and unable to power back on until it was left...

Try pulling the printers plugs (both USB and power) for 20 seconds, this will make sure anything in its memory will be removed (such as a print job that failed).
Also, some printers want to be...

Next time it happens. Get a pen and write down what the error is. It would be something along the lines of:

STOP: 0x000008 SOME_SORT_OF_ERROR

Then repost here. We cant really help you unless we...

Being that this is a DRIVER_IRQL and not just a IRQL then I would say that the problem with this is a driver issue. Did you change any drivers/install new hardware recently?

According to...

Well, when a computer beeps endlessly and doesnt make it to post, it is definitely the ram that has a problem.

As you mentioned you've already tried to diagnose the problem by swapping the ram but...

There is a good writeup at ComputerRepairTalk.com to help you diagnose your rebooting problem (at least so you can see what the Blue screen of death error is):
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