OK. I have found a bit of a problem.
According to Gateway's specifications for the 5200 series says that it doesn't have a graphics slot at all.
According to Gateway's specs for the motherboard that came with the 3.2 P4, it has a PCI-E slot.
I guess you're gonna have to open up your case and check it.
Both sources say that your comp uses PC400 RAM, up to 4 gig in 4 slots.
My Rig: SABLE
Antec 300 Illusion / Antec EarthWatts EA650 650W / EVGA GTX 760 2GB
AMD FX 8320 x8 Black Edition / Gelid Tranquillo / MSI 970A-G43
Sandisk Ultra Plus 128GB / Samsung 840 120GB / WD Black 750GB / WD Green 1TB / WD Red 3TB
G.SKILL Ripjaws 2x2GB DDR3 1600 - Crucial Ballistix Tracer 2x2GB DDR3 1600
Win7 Ult 64-bit - Func MS3 Mouse - CM Storm QuickFire Rapid Mech Keyboard
R.I.P. Danny L. Trotter
... 14 Nov 1945 - 4 Sept 2009