How Much Ram Can Windows XP Run?

[dwane]

Im lookin at put 3 gig of ram in my computer but i herd that windows XP can only run a gig and a half can someon clarify this?

[Fire]

Its dependent upon how much ram your motherboard can run. I dont see why an os would limit ram. Would make most gamers chose not to buy it. Especially with these newer more ram consuming games. So just make sure your motherboard says it can handle it.

[aerobahn]

the max amount a 32bit cpu can address is 4gb.

The a 64bit cpu can address much more.

thus it is not WinXP but the CPU/mobo.

[Fire]

eh.. i was close enough ;p

thx for the info aer0

[MylzDavis1975]

Could you imagine if someone had a computer that had over 4GB of RAM? wow

[Doppelganger]

Originally posted by MylzDavis1975
Could you imagine if someone had a computer that had over 4GB of RAM? wow

yes, i can imagine that. the new athalon 64 chips will be able to use over 4gb, and some multiprocessor servers (i was looking, and one has 24 parsc chips, from sun of course), can adress up to 96gb. the software doesn't limit the memory, the chip does. back in the days of the 16 bit chips, the max was 2 gigs (that was impossible due to mobos though). if there is a 128bit chip, or two 64 bit chips, or 4 32 bit chips, that can hold 16gb of ram.

[InuTrunks]

All NT machines can run as much as your mobo can hold, windows 95 I think can use about 64 it won't use more then that, 98 and ME use 128 (I think). You can have more, but windows won't use it correctly unless it's an NT, (NT, 2k, and XP)

[Doppelganger]

Originally posted by InuTrunks
All NT machines can run as much as your mobo can hold, windows 95 I think can use about 64 it won't use more then that, 98 and ME use 128 (I think). You can have more, but windows won't use it correctly unless it's an NT, (NT, 2k, and XP)

correction, the total processing power in bits. the mobo can only use as much as the total bits the chip(s) use for processing.

[Shauku]

Windows 98and 98SE cannot hold more than 256ram, (well it can but that will slow you machine)

Windows XP cannot hold more than 5.4g ram ( its what i heard, maybe not true) but anyway most Mboard cannot hold more than 4g ram, ( as most of you said too)

[dwane]

thanx for that looks like 3 gig will go in my computer

[jzhang]

just one final comment, if that 3gb of ram is gonna fill up all the ram slots on your motherboard, depending how good your motherboard is, there are serveral possibilities.... like motherboard will reserve some memory so you might get like 2.8gb or something ... of course there is the obvious that your system might not boot because some motherboards are just that crappy ... and then of course there's the postive view, that everything works perfectly...

[dwane]

Well Im Gettin The RAM for free so if it dosent work thats no big problem thanx again for everyones input

[Mithrael]

the max amount a 32bit cpu can address is 4gb.

Yes, you are correct. Others are not. Max is 4gb, however due to limitations in the current architecture design of i686 processors (p4s may or may not be held to this limitation) only 3.5g will be recognized and used. The address space for the top .5gb is reserved in the architecture specification. p4s are built off of that spec with extensions, to maintain complete compatibility they would have to keep that address space reserved as well. Alternatively, they could do a real-time remapping of that space to some other location, but that doesn't seem like the stablest of solutions.

Now that GB simms are easily avaialble, it's not too hard to max out your ram. 4x1g is allowed, but you won't use the top portion of the last slot.

Now... whether or not Windows XP uses this ram efficiently or not is another story. It's optimized to run with 512mb, more is useful, but 3g will likely go to waste. I'd be really surprised if your physical memory usage ever exceeded 25%. Windows will likely still make use of a huge page file (even if there is plenty of room in ram). You might experiment with killing the page file while playing FFXI and see if performance improves without killing stability.

edit: spelling error

[Romance]

Three Gigs of Ram ! What do you use your computer for advanced 3d modeling in 3d studio max or Maya? If you don't having that much ram is almost pointless, oh well I'm just curious

[aerobahn]

Originally posted by Mithrael


Yes, you are correct. Others are not. Max is 4gb, however due to limitations in the current architecture design of i686 processors (p4s may or may not be held to this limitation) only 3.5g will be recognized and used. The address space for the top .5gb is reserved in the architecture specification. p4s are built off of that spec with extensions, to maintain complete compatibility they would have to keep that address space reserved as well. Alternatively, they could do a real-time remapping of that space to some other location, but that doesn't seem like the stablest of solutions.

Now that GB simms are easily avaialble, it's not too hard to max out your ram. 4x1g is allowed, but you won't use the top portion of the last slot.

Now... whether or not Windows XP uses this ram efficiently or not is another story. It's optimized to run with 512mb, more is useful, but 3g will likely go to waste. I'd be really surprised if your physical memory usage ever exceeded 25%. Windows will likely still make use of a huge page file (even if there is plenty of room in ram). You might experiment with killing the page file while playing FFXI and see if performance improves without killing stability.

edit: spelling error

Yes windows will make use of the pagefile no matter how much ram you have free.

As for killing it. The best/only effective way is to turn it down to Zero MB. There by forcing the pagefile onto the ram. In which it can hover to 100~ to 50~mb. Only recomended for people with at least 1 gigabyte of ram.