Motherboard HAS PMS!!!

Hi Guys..

Got a question regarding my pc and its performance...i have a ASUS motherboard with an AMD Athlon 5000+ @ 2.6GHz with 6GB DDR 2 @ 800MHz and an Asus GTX260.

Now! Firstly when i plug in my external seagate HDD it does not pick up at all...not even in disk management, the HDD can be picked up on other people's pc's and other HDD can be picked up on my pc i.e the HDD is perfectly fine.
My iPod ...the same issue.

I can run games but Fallout 3, New Vegas and CRYSIS don't run...i have a steam account and run MODERN WARFARE 2 and BLACK OPS on full graphic settings.

I think its my Motherboard but not too sure, my tasks at the bottom of my screen flash sometimes and my 2 SATA HDDs conflict if the eSATA is plugged in( Front panel )...

This problem sometimes happens...and i format constantly because of this irratating dellema...LOL
Am definatly looking to upgrade Board, CPU and RAM<Any views will be highly appreciated>

Regards