I am reallllly confused, nervous, and actually kinda scared because either my computer has a mind of it's own, or I'm losing my mind?!?! I know how evil Microsoft is...but this is getting ridiculous! HAHA anyways.... I have a Dell Dimension 4600 upgraded it about 3 months ago when I acquired this PC upgraded it to 1GB of RAM and a 150GB SATA HD. Everything else is regular...nothing fancy cause I use this for broadcasting. everything was going OK until...my computer reboots, and/or randomly freezes up until I hold the power button in. Every now and then i get MACHINE_CHECK_FAIL and/or MACHINE_CHECK_EXCEPTION can't remember... I know this is hardware related...but here's the catch.....I have tested each stick of RAM, even disabled the onboard/integrated video card and tried one in the PCI slot. Still does it. What is weird is (not sure if this means ANYTHING) is that when i play sound/music using any media player it reboots. Im thinking it might be the integrated sound card (SoundMax). Which I've tried updating the drivers, but the dell website doesn't really have any. Tomorrow, I am going to try and get another sound card and disable the integrated one and running on the other. If anyone has ANY suggestions before I spend high money on replacing the entire motherboard, please share. :-\ this computer is vital to my radio station! Thanks!