Question about memory troubles.

[enlightenedby42]

So, I've always tinkered with overclocking just a couple hundred mhz or so, and am trying to really wind this thing out finally. The processor is staying under 35C even under load and seems stable with the FSB @ 225. It errors out on Prime 95 torture tests, and I've discovered it takes the error much longer to occur on the processor heavy test than it does the RAM heavy one. I've got a Corsair XMS 2x512 3200C2 kit, which is supposed to run at 2-3-3-4. Have upped this as high as 3-4-4-8, and tried both the alternate ratio settings. Have ulso upped the vcore a tad, to no avail. Am I missing something here or are these just lowsy sticks of ram? I realize there are millions of other n00b questions along these lines floating around here and thank you guys in advance for your patience.
Specs:
Asus P4P800 Deluxe
P4 3.0C Northwood
Zalman CNPS700A
2x512 XMS3200C2
BFG 6800GT (stock)