If so, I am not sure. The card should fit in the x16 slot, but I am not sure if there is an issue with the heat spreader directly below the slot. The 9800 GT you selected is a two slot design that is wider than most 9800 gts and I am not sure if it would clear the heat sink. Also from looking at the picture I cannot tell how tall the heatsink is.
Does you PC case have room for a full sized card? Does the PSU provide enough power?
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:
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.
Biostar is not a top brand in mobos - but better than PC Chips. But it is an older board with AM2+ CPU socket, DDR2 memory slots, and only 2 slots. Will this work with rest of your system? Perhaps you should drop back and start the post over in the New Build forum and include a description of how you use your PC, you budget, and ideas for components.