Windows XP Home only recognizes 2GB of 3GB installed ram

[vanquished]

Hey Everyone,
So I'm trying to redo my old media pc and let a friend have it, I uninstalled everything and formatted the drives and am now in the process of getting it ready. I just installed Windows XP Home (legal) and it is only recognizing 2gb of the 3gb installed PC3200 ram. Perhaps I just haven't used XP in so long that maybe I cant remember if it can't have uneven ram amounts? Anyways...

Here are the specs of the system:
Mobo: Asus A8N-e (4gb max supported)
CPU: AMD Athlong X2 4200+
RAM: 3GB (2 X 1GB, 2 X 512mb) PC 3200
GPU: Nvidia 7900GT KO

So, does anyone know why windows is only recognizing 2gigs of the 3?
Thanks a lot!
-Vanq

 

[chulex67]

No way to really gaurantee that the ram will all work together nicely. In general it is not a good idea to mix ram size/speeds, but you may get lucky and be able to use them all at the same time. Are they at least the same speed? If so, you may get lucky and be able to run them in dual channel.

As for the4 sticks, it is actually the memory controller on the CPU (not the motherboard) that is the problem.

Athlon64 cpus don't typically like 4 sticks of ram. There is a high chance that it will automatically underclock your ram to PC2700 speeds and bump you to a 2T setting.

Personally, I'd stay with 2Gb of ram at PC3200 1T settings. Since most applications wouldn't use more than 2Gb anyways, you'd be better off with fast 2Gb over slower 3Gb.

 

[matt_b]

Have you tried switching location of the RAM sticks on your motherboard? I've had some motherboards in the past where two of the four slots were vacant until down the road come to find out they were dead all along when trying to add two more sticks to the board. Also, some motherboards can be really picky about having different RAM stick sizes being used at once. Do you also have these two sets paired up in the right channels? Not seeing the RAM isn't a function of the OS, but rather your motherboard's ability to utilize them if they are not defective themselves.

 

[vanquished]

Well I know all the slots work because I'm coming off Windows 7 Starter, and when that was installed it recognized the 3gigs of ram but said 2 gb usable (as is the limit on Windows 7 Starter). The ram is all pc3200 but it is different sizes. I suppose I'll just give it a go running 2 gigs of ram then. The curremt ram setup is A1: 1gb, B1: 512mb, A2: 1gb, B2: 512mb so the ram should be in the right corresponding slots for dual channel.

Thanks,
Vanq

 

[matt_b]

So then what happens when you switch what's in the A and B channels? Same thing or only 1 gig (the two 512 sticks) recognized?

 

[vanquished]

Hmm, I'm not sure. Probably would have been good to check unfortunately I'm just seeing this now and I already gave the computer away (as intended). I just left it at 2 gigs and took the 2 512 sticks out.

 

[vanquished]

Best answer selected by vanquished.