Performance penalties for excess RAM? (32-bit Win. XP)

[PGR]

This is such a basic question, but I just can't seem to find an answer to it:

I'm building a new PC around an ASUS P5E64 WS Evolution mobo (Intel MCH X48 Northbridge, DDR3 memory), an Intel Q9550 processor, and 32-bit XP Pro. I should add that I'm not a gamer or an overclocker and my system setup philosophy is to tweak what I have to to eliminate bottlenecks, but not much more.

My core question is simple: Is there any performance penalty for running more RAM than 32-bit XP Pro will recognize?

Unfortunately, I need to stick with the 32-bit version because of existing software constraints, but I'd like to have as much recognized RAM as I can. My first impulse is to stick a matched pair of 2GB DDR3 modules (4GB) in the mobo and just let my OS recognize as much of it as it will. But if that's going to result in a performance penalty over a pair of 1GB modules (2GB), then I'll go with the smaller modules.

Apparently, this mobo has a problem maintaining rated FSB speeds when all four memory sockets are populated so there are no practical RAM configurations between 2 and 4GB. I should also add that 2GB of ram is plenty for my current needs, however I'd like to buy with the future in mind but not if it's going to slow things down now.

So can any of you memory gurus explain this to me?

Thanks ahead of time!

Pete

 

[stoner133]

There is no penalty, its only going to use a little more then 3gb if you put in 4gb but its not going to hurt it.

 

[dechy]

I was in your shoes a while back, stuck with XP32 with 2GB RAM and wanting to get more out of it without spending too much or losing something out of a bad choice.

Well, I did the jump to 4GB on XP32 and system would see 3.25GB using BIOS settings. I'm a pure gamer, and I dual box on the same system, so 2GB just wasn't cutting it anymore. I did some benches before and after and I had gained a very few FPS in almost every game. So no, from my experience, I did not get a loss of performance, the opposite was more true.