I'm curious because I can save ~$100 by downgrading my case, PSU, and MoBo (don't want to) to buy a 570/6970 (2GB) but I know that certain 6950s (2GB) can be unlocked to run 6970 shaders to give similar performance. I just don't know which ones exactly or if I need to spend the extra 30-50 on an unlockable pre-overclocked 6950 (like the MSI Twin Frozr III that I know can be unlocked or the HIS IceQ Turbo X that I don't ). Which, at that point shouldn't I just suck it up, buy cheaper parts and get a non-reference/faster 6970 or 570? This is my first build btw.
Don't bother getting a ref design HD 6950 to unlock it, only the Toxic HD 6950 is still unlockable but it's hard to get these days. Any other HD 6950 without a BIOS switch is still unlockable but the percentage of risk is high.
Non ref designed cards runs cooler, quieter & give more headroom for OCing unlike the ref designed cards they run hooter and noisy.
GTX 570 is slightly faster than HD 6970 (single card vs single card) but the GTX 570 cracks in higher resolutions above 1920x1200 that's give a benefit to the HD 6970.
HD 6950 performs in neck to neck with GTX 560ti but the HD 6950 is lishgtly faster than GTX 560ti, same story for the HD 6970 vs GTX 570 they perform in similarity but the GTX 570 is slightly faster under 1200P resolution.
EDIT: When it comes to CF VS SLI, 2 HD 6950s in CF might perform close to /better than 2 GTX 570s in SLI because the scaling of the HD 6K series is greater than nVidia's GTX 5K series, so HD 6970s in CF outperforms the GTX 570s in SLI.
Okay, so definitely don't buy a reference 6950 to unlock it, right? Even if I overclocked it, a TFIII or other non-reference card (Toxic, wish I could find it) without overclock would run faster and quieter? I've never overclocked before and this is my first ever build so I don't know what it really means to overclock. Like if I buy a reference Sapphire to try and push it to the speed of a 6970, will it naturally have a shorter lifespan?
I'm not quite sure which resolution I'll be using, but probably no higher than 1920x1080.
ASUS 6950 2gb is good model.
You will laugh about few min's because of size of graphic card and heat control.
I do and few of my friend ASUS 6950 is shader unlock.
They are overclock very well and stay nice cooling.
You will like it~
1.25 GB is superb as long as you're not exceeding 1920x1200 resolution. However, some GPUs might not benefit from the extra VRAM so i think that the GTX 570 2.5 GB is useless unless you're running 2500x1600 monitor.