Ram Advice

Fear not, this has nothing to do with male Goats.

I currently have 2x256mb ram paired on my mobo with a spare non paired slot next to them... Now... I want to upgrade to 1gb... So I have two choices...

1. Buy a 512 and put in it the computer.
2. By 2x512, throw the 2x256 out and put the 2x512 in the mobo paired.

Now, I know there's a speed advantage of pairing up which is why I got the 2x256 in the first place, but is it worth it for the extra cost?
Am I going to lose speed by putting a single 512 in or will I just not gain speed.
Will the 2x256 run at one speed and the 512 on it's own run at another... etc etc
You get the general gist of my worry / question I'm sure.

Advice, comments, general insults or money welcome.

check the exact speed and cache latency of your current chips, get a 512MB of the same type and stick in in the spare slot = cheapest. No point getting faster 512Mb for the other slot. however, IF your board can take higher speed RAM (consult manual/web) getting 2x512MB that are faster and chucking the 256MB would be a tiny bit better and more L337, however, I bet if that RAM came with the machine it's running at full speed anyway, as is the case with most PCs.

If you use RAM with different speeds, it will usually use the lowest RAM speed for all of them.

If you add a single 512 to your existing 2x256, you may need to put the 512 module in the first slot (closest to CPU) for best results.

Not sure about the pairing, on this system I've got 4 slots which must be paired up to work efficiently. But, you have 3 slots? which may mean you don't need to pair the modules up. It should tell you in the mobo user manual whether you need to pair the RAM modules.

I'd go for option 2 definitely - if you add your old RAM and it's not exactly matched (which is likely) you'll lose performance.

I bought a matched pair of 512Mb memory sticks from the same manufacturer (Corsair) at the highest speed the Motherboard could handle when I built my system. And I found 1Gb of RAM makes a big difference to performance over 512Mb anyway, because you're not accessing the harddrive nearly as much.

Google is my friend!

I've found the answer it seems... Whoever wrote in to PC Format has exactly the same set up as me (mobo/ram)!

http://www.pcformat.co.uk/tips/default.asp?pagetypeid=2&articleid=34147&subsectionid=682&subsubsectionid=468

so you gonna just stick a new 512Mb like I suggested?

Oh, it's an A7N8X, is it? I had one of those, and it was a bitch to find memory it liked. Asus boards are often very fussy, and very often need identical sticks of ram ( not a matched pair - that's for performance junkies, not compatibility - just two identical sticks. ) By all means just buy the 512, but if it doesn't work or if you start getting out of memory errors and crashes, you'll have to pull the 2x256's back out and get another identical stick of 512.