2 gigs at 800Mhz or 4 gigs at 533mhz? What is best for gaming?

I have a decent rig, C2D overclocked to 3ghz + 7900GT + XP Home. I just bought 2 gigs of nice fast 800mhz DDR2 ram to replace my current 2 gigs of 533mhz.

Would I be better off with less ram (2 gigs) at the higher speed? Or should I include the 533mhz sticks in my setup (which would slow all 4 gigs down to 533mhz?)

Opinions appreciated.

sell the 533 on ebay for about £90 at least that is what i got for my kingston value and buy 2 more gb for about £120

4 GBs wont make too much of a different and the mhz drop you would suffer would not be worth it. Sell the extra ram.

I say overclock the 533 to 800! . Personally I think that you should at least try to see if your current memory can do 800. Depending on the chips used it very well may be able to. My first set of DDR2 (OEM Micron D9s) ran all the way to DDR900.

Overclock the 4gigs! Problem solved!