Please help. I have 4 sticks of DDR2 800MHz memory that are only running at 667MHz. No you did not just time travel back to 2007, yes I know I have an ancient PC. Specs: 2 sticks of OCZ 1GB 6400 2 sticks of PYN 2GB 6400 Please Note: I've tried each pair separately and each pair by themselves will run at 800MHz. EVGA Nvidia 680i mobo (122-CK-NF68) Intel Core 2 duo 2.4 CPU Geforce 285 GTX Windows 8.1 64-bit All default settings, no overclocking, updated mobo BIOS I've checked the mobo's manual and I'm sure I have the placement right (generic brand at 0 & 2, OCZ at 1 &3, tried OCZ on 0 & 2 as well) and I am seeing 6GB of memory during bootup and in Windows. As I said I've tried each pair individually and they will run at 800MHz if it's just the 2GB OCZ pair or just the 4GB generic brand pair. I noticed that if I go into BIOS and change the FSB Memory Clock Mode from 'Auto' to 'Linked' I can change the FSB speed, which changes the memory speed. If I change the FSB from 1066 to 1280 the memory speed changes to 800MHz. This changes my CPU speed as well though from 2400 to 2880. Would these be major changes and would I be pushing my system? Never overclocked anything before. Also, I'm not sure why I'd have to do this to get 800MHz when each pair individually got this speed by default. If I can't fix this then which is better: 4GB @ 800MHz or 6GB @ 667MHz? I'll be using this computer for gaming. It actually can run games from within the past year at decent settings. Any help would be greatly appreciated. Thanks for reading.