Small Computer Upgrade Time - Need Advice!

HKYStormFront

ok, so, my friend got me a copy of Win7 Home Ultimate 64bit for my birthday a few weeks ago. i'm picking it up when i got home next weekend. the idea being that once i go to 64bit windows i will upgrade my RAM. right now i'm running 4 1gb DDR2 (PC6400) dims. my motherboard max's out at 16gb's of RAM. two of the dims are more generic "economy" style crucial boards, the other two are PNY "gaming" ram which has heat syncs built in and a lower latency (or is it higher? i can't remember...). anyway, i'm thinking about picking up 8gb's of RAM. what's my best option?

1) take out all my RAM (and sell it!) and just run two 4gb dims
2) take out all my RAM (and sell it) and run four 2gb dims
3) take out the "cheaper" RAM and put two 4gb dims in for a total of 10gb's

i will eventually be upgrading to either an i5 or i7 chip and motherboard down the road but that won't be anytime soon and i'd like to upgrade to at least 8gb of RAM in the meantime. if i go with #3, will have any hardware conflicts between the two different sizes of RAM? what's your thoughts on it?

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Patrick // 06 Frontier 6spd Nismosis // Mods: Uprev Tuned @ Z1 Motorsports: 257whp & 292 ft lbs
09 Pontiac G8 GXP // M6 // Sunroof // Tint... For now