How much ram can XP address>

[Hermskii]

There it is. Straight and simple. How much ram can Microsoft XP Home and Pro edition actually utilize? I have heard the answer to be 4gb from people I work with.

I have a friend that has 4 gig installed on a very modern mobo but he says it can only see 2.5gb of the total 4gb he has installed. He can then take out that ram and stick it into an older mobo and it will see 3.5gb which is that type of mobo's max ram anyway. What could be his problem with the new mobo only seeing 2.5gb? Thanks.

 

[John]

4GB memory installed but less memory size detected

 

[Nothinman]

What could be his problem with the new mobo only seeing 2.5gb?

Resources required for the motherboard, add-in cards, etc. The values vary for each piece of hardware so you can get different values for each combination you try.

Since MS has artificially limited XP to 4G there's no way to see the 'missing' memory even if you remap it above the 4G mark as most motherboards allow now. If you install Server 2003 it should work since it supports PAE and 8G of memory, but other than that the only real option is 64-bit XP which also isn't limited to 4G or another OS without those restrictions like Linux.

 

[Hermskii]

Thank you.