driver IRQ not less or equal (bluescreen)

Hello everybody'

Can somebody give me some tips to avoid getting a bluescreen??
I get the following message: DRIVER_IRQ_NOT_LESS_OR_EQUAL
It happens 2, 3 times a day to me.
I switched from Logic to Sonar and had this problem immediately from day one I installed Sonar (4.0, 4.0.1, 4.0.2).
I tried everything I could. Reinstalled a dozen times but unfortunatly. I learned to live with it. But It would be a true salvation if somebody could help me fix this problem.

It thought the more programs I run at the same time the higher the chance of getting a blue screen was. But than I'm not a 100% sure.
I always end up mixing the songs in audio with no midi running anymore. Nevertheless the bluescreen problem keeps occurring.
I use AK sys (akai-software for transferring data from PC to sampler)with my sampler (s5000).
And I run Sonar on a P4 3.4 Ghz with 1Gb Ram and 2x200GB HD
Maybe I should put some more memory in the computer, 2GB?

I hope somebody can help me?

Thanks in advance!

Raffa.