For the most part, all graphic card form factors are forward and backwards compatible.
Most PCI graphic cards work in PCI motherboard slots.
Most AGP graphic cards work in AGP motherboard slots.
Most PCI-E graphic cards work in PCI-E motherboard slots.
There are some incompatibility issues, such as AGP 1.5 will not physically fit in AGP 3.3 slots or something silimar. For the most part, as long as the graphic card form factor (PCI, AGP, PCI-E) matches the graphics card slot on the motherboard, the card is compatible.
The most recent issue of incompatibility comes from PCI-E 2.1 graphic cards not working in all PCI-E 1.0 graphic card slots. If your motherboard has a newer chip set, then most likely, it's compatible with all graphic cards.
If you really want to make sure, tell us what motherboard you have and what graphics card you want to install.
This is my first build uh, and I was planning on buying an entire new computer, So this is bound to change since I have a while to accumulate some cash. http://www.newegg.com/Product/Product.aspx?Item=N82E168...
Is the motherboard i'm set at the moment, And I can't seem to find a good graphics for it.
What graphics card you get is going to depend on what CPU you intend to install into that motherboard and how much money you want to spend on the graphics card. That motherboard is compatible with ANY PCI-E graphics card on the market today. Since this is going to be a completely new build, I'll also add that ANY recent generation graphics card is compatible with any new motherboard on the market today.