I have an Intel D945GCLF2 motherboard in a VoomPC enclosure with a M2-ATX 6-24V power supply hooked up to a CID700M. I hear a very loud and distinct noise in the speakers that seems to follow the engine's RPMs. I found another topic of some guy having ground problems in the end, but my power supply is connected directly to the chassis. I'm sure the noise comes from the PC because when I disconnect it, all is fine. It get's it's power directly from the battery. Anyone any ideas?