Quick question about RAM

[ImNeat]

I'm looking to buy a third 512MB RAM chip for my Dell desktop - and will probably go with this one.

I am hesitant, though, because there's a warning in red font:

Installation in matched pairs of modules is recommended, please order quantity two. Although the memory may be installed one module at a time, the best performance comes from installing in matched pairs of modules.

What does this mean? Would it be pointless to order just one and have a total of 3? I don't know very much about hardware, so any help would be much appreciated.

[antidrugue]

This simply refers to the dual channel architecture of DDR2. More about that here :
http://en.wikipedia.org/wiki/Dual_channel

By having 2 identical (same type of RAM and same size) module of RAM (so put in pairs), you can theoretically double the speed it which it threats information.

However, as always with RAM, quantity is more important then speed.

[ImNeat]

Ahhh I see. Thanks much for the reply.

I think I'll still get the 3rd 512 then.

[yourname3232]

Yes, the matched pairs is to support dual channel.

As a side note, dell overcharges for RAM by alot.

You should check out this.

It is RAM with the same specifications as the Dell one, but about $27 less!

[ImNeat]

You should check out this.

The two chips I have are "PC2-3200," the chip on newegg is "PC2-4200," what's the difference? Will both work?

[antidrugue]

As long as it is DDR2 it should work no problem. So PC2-XXXX should all work. Of course, all RAM will be clocked at the frequency of the slower stick.