GPU Upgrade

I'm looking at upgrading my GPU from a AMD Radeon HD 6870 to either a AMD Radeon HD 7870 or 7950. but reading around reviews, Some cards come with 2GB GDDR5 and 3GB GDDR5. My current 6870 has 1GB GDDR5, and Iknow it isn't pulling it's leg with BF3 or Crysis 2 (with the DirectX 11 Patch). Its fine for everything else getting perfect 60fps, on high settings, but BF3 and CR2 it hovers around 45fps and dips to 35fps in rough, fast pace scenes with using high/ultra settings on those games. I have 16GB DDR3 1600MHz Corsair memory and an 8 core AMD FX-8120. So theres nothing there I can think of. If a GPU runs out of memory in it's buffer, does it swap, and page back to the page file on the HDD, or swaps out to main system memory?

I'd wait until the Nvidia 6** Series video cards get released in a few month's. Reason 1: If you've got a 990FX/GX motherboard, it supports both AMD & Nvidia card's. Reason 2: Once Nvidia next series card's hit the market, AMD's HD 7*** series card's prices should drop as competition has arrived. There currently isn't any competition as all All AMD HD 7*** cards beat Nvidia 5** series card's. That very well may change in Nvidia's favor when the 6** series card's hit. Reason 3: All the game's I've seencater to Nvidia's card's, not AMD's. Here's an example, I have a HIS IceQ X Turbo X HD 6950 2.0 GB. video card factory overclocked to a HD 6970. Batman: Arkham City look's 3/4 Black & White, instead of in Color in that game. Furthermore, that's with my monitor/video calibrated with a calibration device.

You sure that your 6950 OC'd is factory overclocked, and not Just on of those BIoS hacks to bring it from a 6950 to a 6970? Also I think Batman: Arkham City is supposed look like that, it has a lot of Black & White and grey washout, I think it's a dark game.

It is factory overclocked @880 mhz. & 1300 mhz.. I believe it has the HD 6970 bios too.Here's HIS's link for it. http://www.hisdigital.com/us/product2-613.shtml I will say it had the highest setting's of all overclocked HD 6950's. Higher than both Asus and MSI. Only thing is HIS only has one fan on it and they set it too low. I've got mine running @ 80%. That keeps it in the 40's instead of 70's at stock fan settings.http://www.hisdigital.com/us/product2-613.shtml