What is the maximum DDR RAM memory XP Pro will see and or use? I have 512MG now, but wish to add more. I know the motherboard has limits. Thank you.
It’s mobo dependent. You will have to look at your mobo info.
You can go to www.crucial.com and do a scan and it will tell you what slots are being used and memory slots available . they also suggest what to add.
Any board will handle 2 sticks of 1024. Limiting yourself to 2 sticks will also provide the best speed and bandwidth on most boards. Current prices on pairs of 1024 DDR are pretty good. It’s also extremely unlikely that you will ever need more than that.
Most boards will lower clock speed and/or timings if you run more than 2 sticks.