PureOverclock ran some tests comparing a standard 256MB 7800GT and a 512MB version.  With some judicious use of NiBiTor, all clock speeds were rendered equal.  Read on to see if paying for that extra RAM is really worth it.
“Does a 512MB framebuffer make any difference? I don’t believe anyone reading this would disagree that 512MB cards will become a firm requirement of high end gaming very soon, but the key question here is do 512MB framebuffers offer anything to us now, other than future proofing?”

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