Stupid question from a forgetting mind

With the release of the nForce 3 chipset, with AGP 8X support, are there really any drawbacks with picking an Opteron CPU instead of an Athlon 64, to play games with?
The question just hit me a few days ago, could anyone try to answer this silly question?

My system: Intel Pentium 4 3.0, 800FSB / TwinMOS 1Gb DDR400 / MSI 875P Neo / Sapphire Radeon 9800Pro / Antec TruePower 550W / 2x Western Digital Raptor / Hercules G.T XP /
SamsungDVD / Lite-On CDRW

Opteron will only run with ECC ram? That's a point in not to buy it. Not that ECC memory is much more expensive than normal memory, but if I am to sell my current PC3200 in favor of PC2700 ECC memory, then it will sure cost me some more money.

My system: Intel Pentium 4 3.0, 800FSB / TwinMOS 1Gb DDR400 / MSI 875P Neo / Sapphire Radeon 9800Pro / Antec TruePower 550W / 2x Western Digital Raptor / Hercules G.T XP /
SamsungDVD / Lite-On CDRW

Is that the same for all server CPU's, that they require ECC memory?

That about the stability I knew. It'll be nice to see some sort of comparison between Opteron and Athlon 64 in games, to see if Athlon 64 really offers that much better price/performance, or if I'd be inclined to save up for Opteron
Or maybe I'll go for the Prescott. I'll probably wait until the Prescott comes out anyways, to see which CPU that seems to be the best for the upcoming year.

My system: Intel Pentium 4 3.0, 800FSB / TwinMOS 1Gb DDR400 / MSI 875P Neo / Sapphire Radeon 9800Pro / Antec TruePower 550W / 2x Western Digital Raptor / Hercules G.T XP /
SamsungDVD / Lite-On CDRW

Yeah, that's pretty contradictional

Though I'm starting to believe in Athlon 64. AMD seems able to clock the core very high now, so I wouldn't be surprised if it'd be a contender to Prescott.

My system: Intel Pentium 4 3.0, 800FSB / TwinMOS 1Gb DDR400 / MSI 875P Neo / Sapphire Radeon 9800Pro / Antec TruePower 550W / 2x Western Digital Raptor / Hercules G.T XP /
SamsungDVD / Lite-On CDRW