A good 500w PSU is more than enough for a 9800GT - unless perhaps you plan a heavy overclock your video card or CPU. I am not familiar with the xtec PSU - which is enough reason for me to counsel wariness in getting it. This would be a good not too expensive option:
Corsair Builder Series 500w - $40 AR with free shippinghttp://www.newegg.com/Product/Product.aspx?Item=N82E16817139018
PC Chips is also not a common choice for mobo - do you already have it or plan to purchase? If you have it, you might just visually inspect to see if the heat spreader I talked about above - it is gold in color in the pic - would conflict with the card you chose. Notice how wide the card is and that it will take up two slots.