Premiere Pro CS5.5/ Adobe Media Encoder Crash sometimes when rendering exporting.

Ok, so in either a rendering, or an exporting Premiere Pro CS5.5 project, or in the case of exporting media, also Media Encoder exporting file, my PC will unexplicably shut down. Just cut off, then slowly start itself back up. I shoot on the Panason Lumix GH2 (unhacked), so I work with raw MTS files just dropped on the tmelne, usually usng effects lke Neat Vdeo, Magic Bullet Colorista II, and Mercalli V2 on several clips all at once(apparently I shoot for these wonderful plugins to fix my lazy shooting mistakes in post).This usually happens with efects laden projects, projects I need done all the time dur to the nature of my job as a freelance video editor.

Running Windows 7 64-bit Professional Intel Core i7 930 @ stock 2.8 GHz 22 GB 1333 Mhz RAM Geforce GTS 250 Adobe Premiere Pro CS5.5 w/ Mainconcept Hardware Codec for boosted editing/ export

I seem to have found the points whenver the the PC crashes to reboot by paying attention to the performance windows of task manager. How do I stop Premiere Pro CS5.5, or Media Encoder, from pushing the CPU cores to 100%, becuase whenever the projects are rendering, or exporting, and the CPUs reach to 100%, everything cuts off. Should I transcode to a lighter, uncompressed editng codec like Cineform? How about dropping the Mainconcept renderer for my Geforce GTS 250, would that be any help.BTW, lowering the bitrate in exporting media in both Prmeire or Media encoder doesn' help, and most projects still reach 100% CPU power. Do I need a water cooler, the CPU temps do reach 115 degrees Farenheit when being pushed hard. Would a monster CPU liqud cooler make a differnece?

Its so frsutrating to have a beast computer for everything else, when the one thing you built it to do properly and efficiently causes it to commit suicide every now and then with an effects heavy project. PLEASE HELP!!!