Sure. As long as you have, say an ATX motherboard and an ATX PSU, the wattage capacity of the PSU is irrelevant to the motherboard. It only cares that there's enough power for the CPU and anything connected directly to it, so as long as the PSU can do that, the motherboard doesn't matter.
I do have to echo Bob's comments however. You can find many better video cards for very cheap these days. Unless there's some specific reason why you're planning to use a 9800GT, like someone gave it to you for free, you could probably get something significantly better in pretty much every way for less than $50US.
Hi guys, I'm planning on upgrading my PSU to a 430w PSU so I can use a nvidia 9800 gt with my computer but I don't know if my motherboard would be able to handle it.
Here is my mobo: http://ark.intel.com/products/52806/Intel-BD82H61-PCH
Here is the gfx card I'm planning on getting: http://www.geforce.com/hardware/desktop-gpus/geforce-9800gt