Even though things are solved I'll go ahead and give you the information just to see if your thought that it would be able to support the card without a new PSU (which is one of the first thoughts I had).
Now, pardon any mistakes here; this is the first new desktop I've purchased in ages; last time I bought one AGP was the new up and coming amazing technology and the original AMD Athlon was about to blow Intel out of the water. Seeing Intel quad-cores and things that used to be on the servers at work...yeah. I've been out of the loop.
According to the packaging, the Gateway comes with a total of four "
PCI Express" (or "
PCI xPress"/"
PCIe") slots. One of them is labeled as being as "
PCIe X16"/"PCI Express X16". ...to me, it looks like a regular old PCI slot, but it's blue. Same number of pins. The other three are tiny little things - apparently "
PCI Express X1" slots. Again, my apologies - this is all REALLY new to me.
Amusingly, the area of my MoBo in question looks almost exactly like this, without the traditional PCI slots:
http://www.geeks.com/techtips/2006/Images/motherboard.gif
The card I purchased was a XFX Radeon HD 6770 with one GB of GDDR5 SDRAM. Now, I probably should've done my homework a bit more - but the box said nothing about the card needing a power supply, just that particular X16 slot. I figured, "hey, my PC has one, I can't believe they're
still doing integrated graphics, I'm switching it out. Should be easy as pie". Well, that's when I found that nice little six-prong plug at the end of the card.
Honestly, I never tried running the PC to see if it worked without the new PSU. Even if it did, however, I'm just glad to have updated the PSU from that stock no-name box. Honestly, what PSU's removal instructions include "rip out of chassis to remove"? Lord.
On a quick side note; I know it doesn't really fit with this section, but do you know what these PCI Express X1 slots are good for? So far one is filled - Gateway installed a wireless card in it which I removed. Can I use this to add a better sound card, or is it really just for tiny things?
Thanks for the interest and the help, randomkid.