tech support being snotty is not a good reason to distrust them....
if you think troubleshooting this problem just won't work, then it's probably your motherboard that is the problem....i think you have a nice processor, you need a motherboard with an intel chipset...i don't know if the 550 is socket 370, but if it is, the cusl2 is a good board with the option of a 1ghz....
however, i really think that you may be able to solve this problem without replacing any hardware...there are certain aspects of your system that i don't have any experience with.....and i'm assuming all along that you don't have any programs running besides the aark control panel and your recording software, and explorer of course....have you done a search for reviews of your motherboard? or for the chipset?
but this is probably pointless, cause DFI motherboard is probably crap as is the chipset...if you get an asus that can fit your form factor , then you can get everything working for a hundred or so...but go amd if ya wanna, i''m not........not yet anyway