hey if i get a radeon 9800pro will i have any troubles with a 220w psu for my shuttle sb62g2? also which brand of the 9800 shall i go for gygabite/connect3d/crucial/saphire etc etc?
Well, a number of people have run high-end cards like that in their SFF systems without a problem. It seems those PSU's are made like the ones in rack-mount servers, so they going to be fine. As for brand, ATi's own cards do just fine, but if you're not looking at them, I'd look at Gigabyte and Crucial first, then Sapphire.
whats the advantages of the gygabites or crucials over the default ati one? anything about noise or heat?
Well for the psu. Personnally I had a Antec 350 watts and I had to change it in order to use my graphic card. As for the brand of your card. I'm not sure about the other advantages but one advantage would certainly be the price. Built By Ati cards have a tendency to cost a lot compared to the Powered By Ati cards.