A few simple things to check. Look up the datasheet on your processor. What is the highest memory speed your processor supports. Then look up the data sheet on your motherboard, find out the highest speed your motherboard supports, and then look at your memory. Your memory should ideally be at the same speed as the slowest of the two (ideally both of them will have the same cap). Also, if you built your own computer, check the timings on the memory vs. factory requirements and in the BIOS. You might have memory performing at a lower speed.
Video card wise, if everything checks out fine, and you're still getting low framerates it could be your video. Some of the low-mid range cards can run decent settings at a high res. If you're wanting to push 1080p at Max, you'll want to have a decent mid to high range card, but before you make that investment, make sure you look at the whole machine as a whole.
WoW Blackhand-US-Date of Retirement: 9/21/2010... /Sigh
Devari - 90 Rogue 85 DK Druid/Mage/Warrior 70+
FFXI - Shiva "Retired.... Or not? One more try, honest."
Desmar - 65 Sam 36 Mnk 18 Thf 12 War
FFXIV - Devari Garamond - Sargatanas 50 Paladin / Culinarian / Weaver / Armorer
Beta - Devaria Ariadne - Ultros - Pugilist