[J3Vr6]

I was looking at memory for my computer, the one the guy at work gave me, and the instructions to the motherboard say it supports DDR DRAM PC1600/PC2100/PC2700 and has a footnote to the 2700 that states:

"Because the quality of PC2700 module is varied, we don't recommend you to use 3 pcs of PC2700 module at the same time".

I was just curious on what the difference was between pc2100 and pc2700.  I tried to search online but nothing really gave me an explanation.  And, based on the footnote, should I assume that pc2700 isn't that stable or something?

[Admiral LSD]

About 600Mb/s of theoretical bandwidth (PC2700 has 2.7Gb/s while 2100 only has 2.1), that's it.

Your motherboard manual was probably printed when 2700 was just starting to come out and, like 3200 a while back, the first generations of modules were unstable but both 3200 and 2700 have been out for long enough now for that not to be a problem. Ultimately though the limiting factor will be the FSB of the CPU. Although most chipsets/motherboards allow you to set the RAM and FSB speeds independently for best performance it's advisable to keep the two in sync. If you only have a 133Mhz FSB CPU regardless of whether you buy 2100 or 2700 you'll most likely be running it at 2100 speed anyway (3200 should still work btw, just not at 200Mhz but since you don't have a 200Mhz board/chip it shouldn't be a problem. It may even be cheaper as well).

[IceFire]

PC2700's are so common now the quality isn't an issue.  As stated above although in perhaps more complex terms, the speed of a PC2100 stick is 266mhz (133x2 - thus the Double Data Rate or DDR) and the PC2700's are 333mhz.

If your board supports it, no problems.  Just provide the store you go asking for with the specs and they will find the stuff you need (or they should).

[J3Vr6]

The manual of the motherboard says:

"200/266mhz FSB and DDR bus speeds"

So what does that tell you?  Would 3200 or 2700 work as they should or would they be bottlenecked?

[diamondgeezer]

Well the 3200 would be no good as your first post said the board didn't support it. Stick with the 2100 says I. For one thing it's dirt cheap, so you can get obscene ammonts of it

[IceFire]

Sounds like PC2700 wouldn't gain you much....might as well get the PC2100 as Diamond suggests.  That way your running at the same speed as your memory bus and presumably at the same speed as the ram already in there.