Question about RAM usage in Windows 7?

[Jihi]

I'm sure my ignorance of computer hardware is about to show but I don't where else to ask what is I'm sure is a fairly simple question..

So I'm using Windows 7 Ultimate 32bit. I have 8gb of RAM installed on this system. Windows is reporting all 8gb's but is also saying only 3gb's are useable. I also apparently have a 6gb page file now. Googling a little I've gathered that 32bit OS's are only capable of using 3gb's and that this is normal, but that the other 5gb's aren't going completely to waste. Windows is doing... something with it? That's the part I'm having trouble understanding.

Can one of our resident computer experts explain this? Preferably using short words and simple sentences? Is the other 5gb being used and if so how? Do I need to invest in a 64bit OS to get full use of all 8gb?

[Duckster]

You are mixing RAM with hard drive space.

• 32-bit Windows 7 can only access about 3 GB of RAM. It's possible that your graphics card may be using some of the unused RAM, but it has nothing to do with Windows.
• Your pagefile is using 5 GB of hard disk space.

If you want to take advantage of the 5 GB of unused RAM, you need to upgrade to 64-bit Windows 7.

[HardlySanguine]

Assuming your processor will support 64-bit.

[sevenwood]

You are correct. According to this Microsoft article 32-bit Windows systems can address a maximum of 4GB of memory and individual apps running under those OSs can access a maximum of 3GB of memory.

According to this article 64-bit versions of Windows can apparently access up to 192GB of main memory. Note that unless you're running many, many copies of 32-bit application software simultaneously you really need to be using 64-bit application software to use up this much memory.

[aceplace57]

You're memory usage is very high. My Win 7 PC uses about 850MB of RAM. Double what my XP laptop uses, 450 MB.

I have 4 GB in my Win 7 PC. Even with several things open I've never seen it use more than 1 1/2 Gig. I'm using Firefox, Word, Excel, a Slideshow program etc.

Video editing uses a lot of memory. Photoshop can if you have a lot of projects open.

High memory use is often caused my malware or viruses. I'd check task manager to see what's eating up your memory. ctrl-shift-esc process tab

[Jihi]

Originally Posted by aceplace57

You're memory usage is very high. My Win 7 PC uses about 850MB of RAM. Double what my XP laptop uses, 450 MB.

Oh no, I didn't mean it was using 3GB. I just a did quick tally and my task manager is showing about 600MB in use currently. That's firefox, the steam app and a couple of other things.

When I opened the basic system info screen, (control panel>system), it's reporting...

Installed Memory (RAM): 8.00 GB (2.99 usable)

That's what I was asking about.

I don't have any any malware or viruses I'm pretty sure. I don't think I've come anywhere near 3GB in actual use. My system runs beautifully and I've never had any issues with it. This thread was more about just satisfying my own curiosity.

And I did not know that about the page file. For some reason I had always associated with it physical RAM. Learn something new everyday.

[Hermitian]

Originally Posted by HardlySanguine

Assuming your processor will support 64-bit.

I could be wrong, but I would guess that any motherboard that could accept 8 GB of memory would not run a 32-bit only processor.

[jz78817]

32-bit client versions of Windows are hard limited to seeing 4.0 GB of RAM and no more than that. You are letting half of the RAM you have installed sit idle. You need the 64-bit version if you want to make use of all 8 GB.

http://arstechnica.com/ask-ars/2011/...-go-64-bit.ars

key point:

"It wasn't always this way; Windows 2000 and the Windows XP with no service packs installed both set the limit simply to 4GiB total memory, and will use full 64-bit addresses if necessary. Unfortunately, some hardware vendors (notably NVIDIA, though others are also claimed to be responsible) had bugs in their drivers, such that they assumed physical addresses would never use more than 32 bits. When used in a system that required full 64-bit addressing, the drivers would end up corrupting memory and crashing. Rather than forcing hardware vendors to fix their broken software, Microsoft restricted 32-bit desktop Windows to 32-bit addressing (though server versions, with drivers that were in theory server-grade, were never subject to this restriction). "

[Jihi]

Originally Posted by Hermitian

I could be wrong, but I would guess that any motherboard that could accept 8 GB of memory would not run a 32-bit only processor.

I have no doubt my processor could do 64-bit. It's an i5 quad. In fact this is the exact processor I'm currently running. I'm just not sure about shelling out another $100 for another version of Windows 7 when I honestly have no compelling reason to do so.

[jz78817]

Originally Posted by Jihi

I have no doubt my processor could do 64-bit. It's an i5 quad. In fact this is the exact processor I'm currently running. I'm just not sure about shelling out another $100 for another version of Windows 7 when I honestly have no compelling reason to do so.

1) wasting half of the RAM you paid for isn't "compelling?"

2) if it's a retail copy of Ultimate (or even an OEM) you can probably use the same product key for the 64-bit version. you just need to get hold of a disc or image.

[Absolute]

It's not just Ultimate. My retail copy of Home Premium came with a 32-bit disk and a 64-bit disk.

[njtt]

If I may piggyback on this thread a bit, I do have 64bit Windows 7, and 4 GB of installed RAM. However, according to My Computer->Properties, only 3.74 GB of this RAM is "usable". Why would that be? That is way more RAM than I had in my whole computer a dozen years ago, apparently going to waste. But anyway, if 64 bit Windows can address 192 GB, why can't mine use a full 4?

[jz78817]

Originally Posted by njtt

If I may piggyback on this thread a bit, I do have 64bit Windows 7, and 4 GB of installed RAM. However, according to My Computer->Properties, only 3.74 GB of this RAM is "usable". Why would that be? That is way more RAM than I had in my whole computer a dozen years ago, apparently going to waste. But anyway, if 64 bit Windows can address 192 GB, why can't mine use a full 4?

could be a chipset or BIOS limitation. some of the early/transitional 64-bit hardware (e.g. early Athlon 64 and Pentium D) had a hard limit of 4 GB in the chipset and can't remap addresses.

[goldmund]

Actually, (some) 32 bit versions of Windows can allow you to use more than 4GB of RAM. While a 32 bit address space does limit memory addresses to 2^32 bytes of memory, or 4GB, Physical Address Extension will allow the OS to address more than 4GB of memory using page tables.

Sadly, desktop versions of Windows are still limited to 4GB of memory, due to licensing restrictions. For server versions (and apparently according to this page, Windows 7?) PAE can be enabled. While the OS can then address more than 4GB of memory, each individual process/application is still limited to 4GB, unless it supports Address Windowing Extensions.

njtt, the reason that you your OS reports less than 4GB of memory installed is that some of the memory address space is reserved for all the various devices in your system. Since there's only 32 bits of address space, this has became a problem as machines started approaching, and surpassing, 4GB of RAM. So, this extra memory, while not actually used for anything, doesn't have anywhere left to be mapped to within the address space. This is not a problem with a 64 bit address space (1.84467441 × 10^19 bytes), hence 64 bit versions of windows won't "eat" this extra memory on you.

Jihi, if you purchased Windows 7 separately from your machine, you should have received both 32bit and 64bit install discs. If it came installed on your machine by the OEM, they should have installed a 64 bit OS if you had 8GB of memory. Did you purchase a machine with a 32 bit OS on it and upgrade later?

Either way, if you do not have a 32 bit install disc, you should contact the manufacturer if you purchased a machine with an OEM Windows install, or otherwise contact Microsoft. They should be able to provide you with 64 bit install media (likely for a nominal fee). There are various "unofficial" ways out there to get PAE to work on any modern version of Windows, and get half-arsed support for over 4GB memory, but IMO it's not really worth it, 64 bit is the way to go moving forward.

ETA: I may be talking out my rear end regarding the licensing limit for 4GB on desktop 32 bit Windows. There may very well have been some technical reason; I'm primarly a UNIX / Linux guy.

[AHarris]

Originally Posted by njtt

If I may piggyback on this thread a bit, I do have 64bit Windows 7, and 4 GB of installed RAM. However, according to My Computer->Properties, only 3.74 GB of this RAM is "usable". Why would that be? That is way more RAM than I had in my whole computer a dozen years ago, apparently going to waste. But anyway, if 64 bit Windows can address 192 GB, why can't mine use a full 4?

This is expected behavior. Depending on what else is installed in your computer, the system will reserve memory for those devices (and reports it as non-usable memory). The issue is that Windows is preventing itself from addressing that RAM, not that it can't.

See: http://support.microsoft.com/kb/978610

[Jihi]

Jihi, if you purchased Windows 7 separately from your machine, you should have received both 32bit and 64bit install discs. If it came installed on your machine by the OEM, they should have installed a 64 bit OS if you had 8GB of memory. Did you purchase a machine with a 32 bit OS on it and upgrade later?

My machine isn't prefab, I built it from parts without knowing about the 4GB restriction. (I'm not completely ignorant of computer technology, I just have some weird gaps in my knowledge.) The version of Windows 7 I have was a used OEM disc I purchased cheap from a local dealer who isn't even in business anymore. It probably wasn't completely legal, but there it is. I've had it for awhile now. (My old CPU was definitely not 64-bit compatible.) I'm definitely interested in upgrading sooner rather than later, but it's just not a priority right this minute.

As an aside I just want to thank everyone who's responded to my questions, this thread has been very informative.

[yabob]

Originally Posted by AHarris

This is expected behavior. Depending on what else is installed in your computer, the system will reserve memory for those devices (and reports it as non-usable memory). The issue is that Windows is preventing itself from addressing that RAM, not that it can't.

See: http://support.microsoft.com/kb/978610

And the likely culprit would be that you are using on-board graphics.

[DWMarch]

Originally Posted by Jihi

My machine isn't prefab, I built it from parts without knowing about the 4GB restriction. (I'm not completely ignorant of computer technology, I just have some weird gaps in my knowledge.) The version of Windows 7 I have was a used OEM disc I purchased cheap from a local dealer who isn't even in business anymore. It probably wasn't completely legal, but there it is.

If your OEM dealer sold you any of the hardware you used to put your machine together it's legal enough for MS. The disc itself could even be a burnt one and still be legit- say for example you used MS's Ultimate Steal promo and downloaded 7- you're still good to go. All that matters is your product key. Install source is not a concern. MS knows well that thousands of people a day go on torrent sites and download various versions of Windows. They know this will never stop, no matter what they do. Thus, they don't especially care if you get it from a store, a friend or a torrent.

You would have to do a clean install, since Win7 won't let you upgrade from 32 to 64 bits. But if you have a legit key and Windows activation gives you a hassle all you have to do is phone them, tell them your copy of Windows is on one computer and one computer only and they will settle it for you.

[BigT]

Agreed. Just borrow or download the 64-bit OEM version of your particular Windows 7 flavor, and install with the key you already have. But before you do so, use the documents and setting wizard to get all your settings, so you can restore them after the reinstall. Then all you'll have left is reinstalling your programs, and moving your documents back from the backup folders.

BTW, all versions of Windows from Vista on actually use your idle memory, by preloading what it thinks you will most likely need. It doesn't take any more time to write over that memory than it does to write over blank memory, so at worse it will just be as slow as if Windows didn't do that, and at best it will eliminate your harddrive as the bottleneck.