Maximum Memory that Windows XP Home/Pro can support?

Fuddy12345

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Hello. First of all... I know there are probably other posts that asked the same question but I still can't find a good answer...

Currently I have Windows XP Home Edition. I want to upgrade to 4GB of RAM. I can get all the motherboard stuff sorted out, just need help with the RAM. So I want to know if Windows XP Home will support/recognize that 4GB of RAM. If not, will Windows XP Professional Support it? I have XP Pro available.

Thanks.

About the best answer:

There were a lot of good answers so I thank everyone who posted. I just chose the first "most-clearest" answer as the best.
 
Solution
If your running a 32 bit version of windows xp home/pro then you won't be able to use all 4 gigs. It will still be compatible in the sense the computer will run but the amount of memory that will be available to windows will be less than 4GB.

There is no hard limit as mentioned above. the amount of memory that windows will see will depend on the other "memory mapped" hardware in your system. And I believe there are also certain software options you can play around with to increase the amt of memory available to windows (memory remap?).

I am still running XP pro 32 bit on my machine and I can see about 3.25 GB of RAM in windows.

To get a full 4GB and higher you would need to upgrade to a 64 bit OS. As Hellboy mentioned XP 64 had...

Hellboy

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wrong

32 bit has a 3.5 mb limit


windows xp home and xp pro will only go up to 3.5

if you need to utilize the whole 4gb goto Windows 7 64 bit... as xp 64 was a bit of a failure.
 

Fuddy12345

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3.5mb limit haha.. Buy yeah, im pretty sure the 3.5GB is right cause I heard it on more posts. I never heard of 2.5GB.. that just seems wierd.

Thanks for the help.
 

Fuddy12345

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Can you please tell me more about your other PC? Cause If i buy 4GB of RAM.. I wanna know that I am gonna get 4GB of RAM (OR at least 3.5GB in this case)
 

scudst0rm

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If your running a 32 bit version of windows xp home/pro then you won't be able to use all 4 gigs. It will still be compatible in the sense the computer will run but the amount of memory that will be available to windows will be less than 4GB.

There is no hard limit as mentioned above. the amount of memory that windows will see will depend on the other "memory mapped" hardware in your system. And I believe there are also certain software options you can play around with to increase the amt of memory available to windows (memory remap?).

I am still running XP pro 32 bit on my machine and I can see about 3.25 GB of RAM in windows.

To get a full 4GB and higher you would need to upgrade to a 64 bit OS. As Hellboy mentioned XP 64 had really bad support so I would also recommend Windows 7 64 bit.
 
Solution

Fuddy12345

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I'm pretty sure I have 32bit. Thanks. As long as I don't get like 2GB RAM out of it I am happy.
 

Fuddy12345

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I don't think it will take too much. My new motherboard that I am buying has a Geforce 8100.. Im just gonna disable that and use my 8400GS.
 
32 bit will address 4 gig of memory max. But you must count in all your memory in your system, like your video card for instance. System/hardware memory will be assigned address space first. Then whatever is left over up to 4gig will be addressed as RAM.
That usually means for most people who have a 512 meg video card, you end up with about 3.2~3.3 gig of memory. If you have a 1 gig video card, then bingo, there goes another 512meg from your main RAM, so you end up with about 2.5~2.7 gig of RAM that windows can use. (There are other things in your system that have memory besides the video card)
 

pat

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everything in a computer need adresses space in order for the system to access them. BIOS needs addresses, USB ports need addresses, sound, video, LAN, WI-FI,... all of them need addresses. 32 bits system can count up to 4GB adresses. The exact number is 4294967296(2^32) individual adress. So, the more stuff you add to your computer, the more this number is going down. And once every card and other stuff is configured, then what remain is allocated to memory. that's why most computer showes 3.5 GB, but more stuffed one can show less.
 

Fuddy12345

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Alright thanks.