HELP - where has my PC memory gone???

[TopLoser]

Ok...

my old Dell desktop finally started to worry me, it's over 5 years old and must be on the verge of going pop. It was running fine with Windows 10 Pro 32 with 4GB. Years worth of apps and data installed on the SSD that I've been dreading migrating for ages.

Pulled a spare Lenovo box out of the pile, an 8GB and a 4GB memory stick in it. Chucked the Dell SSD in it  and bugger me if Windows 10 didn't handle the change of hardware magnificently - it displayed 'getting things ready' for a few minutes then booted up with all my apps and data intact and all new drivers installed for the new hardware. I never had to touch a thing, easiest migration EVER. Device manager showed everything was happy, all the new bits and pieces installed and working ok.

BUT...

Task manger shows 12.0GB DDR3 installed, but only 1.7GB available to Windows. I see 10.3GB is 'hardware reserved'. What's that all about???

There is a Radeon  R7 + R7 240 display card in there which I assume is taking 2GB - what's happened to the rest?

[Monkeh]

You're going to need a 64-bit OS.

Windows will only let you have 4GB, minus certain reserved areas - and then your GPU's taking 2GB of that.

[timgiles]

You are using a 32 bit version of Windows so you are limited to 4Gb. I thought MS were only doing Win 10 in 64 bit - must be a brain fart on my end.

I don't think you can upgrade easily - but would be worth googling. You can't be the only person who needs this type of upgrade.

Good luck

[TopLoser]

I had a feeling that was going to crop up and bite me...

And there's no way to go to 64 bits without a clean install of Windows 10 and then a complete reinstall of all the apps and other crap...

Video card is going in the bin then!!

[Monkeh]

That will help, but you'll still be stuck with 4GB - ~300MB - VRAM.

[TopLoser]

Pulling out the 8GB stick and leaving just the 4GB in place gives me 2.2GB instead of 1.7GB.

What a giggle eh!

(is it about now somebody mentions Unix?)

[Monkeh]

I wasn't going to. But yes, other OSes allow you to actually use PAE.

That's an.. interesting allocation issue.

[Kevman]

There are hacks to enable PAE in Windows 7 and 8, you might be able to find one for 10 with some googling.

You're much better off installing Windows 10 64 bit, though. Even with PAE enabled, each individual process will still be limited to 2 gig, and PAE itself is a pile of hacks and has had stability problems regardless of OS.

Linus Torvalds had a bit to say about it:
https://cl4ssic4l.wordpress.com/2011/05/24/linus-torvalds-about-pae/

With a 32 bit OS, All processes are limited to 2 gig each.
With 64 bit, 32 bit processes are limited to 4 gig and 64 gig have no practical limits.

[Monkeh]

PAE is already enabled. You can't run 10 without PAE. It just won't utilise it because they're scared of introducing bugs in horribly written old drivers which aren't even signed to run on the OS..

[TopLoser]

I'm fine with 4GB, just looked inside my old Dell and it only had 2GB installed. God knows what the on board graphics were stealing from that!

I'll worry about the 32-64 bit migration in another 5 years time when this PC starts worry me...

[rdl]

You can get video cards that have their own memory pretty cheap and not have to worry about the video stealing from system RAM. I have a 32 bit Windows machine with only 2GB of RAM. When I retired it from gaming years back, I put a 1 GB fanless Nvidia card in it to replace the loud, hot gaming video card it had originally. I think it cost less than $25.

[Monkeh]

You can get video cards that have their own memory pretty cheap and not have to worry about the video stealing from system RAM. I have a 32 bit Windows machine with only 2GB of RAM. When I retired it from gaming years back, I put a 1 GB fanless Nvidia card in it to replace the loud, hot gaming video card it had originally. I think it cost less than $25.

But on a 32-bit system they're still going to murder your address space.

[nctnico]

There are hacks to enable PAE in Windows 7 and 8, you might be able to find one for 10 with some googling.

You're much better off installing Windows 10 64 bit, though. Even with PAE enabled, each individual process will still be limited to 2 gig, and PAE itself is a pile of hacks and has had stability problems regardless of OS.

Linus Torvalds had a bit to say about it:
https://cl4ssic4l.wordpress.com/2011/05/24/linus-torvalds-about-pae/

Linus is wrong about many things and PAE being bad is one of them. PAE works perfectly fine. If you have stability problems then your memory is faulty and needs replacing. I don't get why Windows doesn't have PAE out of the box because a 64bit OS isn't always a blessing due to incompatible libraries and so on.

[edavid]

The PAE patch for Windows 10 32 bit is located here:  https://github.com/wj32/PatchPae2

[Monkeh]

I don't get why Windows doesn't have PAE out of the box because a 64bit OS isn't always a blessing due to incompatible libraries and so on.

Because of incompatible, shitty drivers, which nobody can fix.

If your libraries are incompatible with 64-bit systems, they're either crap or old: Get rid of them.

[edavid]

I don't get why Windows doesn't have PAE out of the box because a 64bit OS isn't always a blessing due to incompatible libraries and so on.

Because of incompatible, shitty drivers, which nobody can fix.

I've been running Windows 7 32 bit + PAE for years, and I have yet to run into one of those drivers.  Can you name a few examples?

[Monkeh]

I don't get why Windows doesn't have PAE out of the box because a 64bit OS isn't always a blessing due to incompatible libraries and so on.

Because of incompatible, shitty drivers, which nobody can fix.

I've been running Windows 7 32 bit + PAE for years, and I have yet to run into one of those drivers.  Can you name a few examples?

No, I can't. And none of them will be modern, signed drivers. Still, that is the excuse from Microsoft. It's a terrible one, but that's the given reason for hobbling 32-bit desktop OSes.

I'm fairly okay with it, because 32-bit should've died a decade ago.

[nctnico]

I don't get why Windows doesn't have PAE out of the box because a 64bit OS isn't always a blessing due to incompatible libraries and so on.

Because of incompatible, shitty drivers, which nobody can fix.

I've been running Windows 7 32 bit + PAE for years, and I have yet to run into one of those drivers.  Can you name a few examples?

No, I can't. And none of them will be modern, signed drivers. Still, that is the excuse from Microsoft. It's a terrible one, but that's the given reason for hobbling 32-bit desktop OSes.

I'm fairly okay with it, because 32-bit should've died a decade ago.

I disagree. 64bit became useable recently. Before that lots of problems with incompatible software. I don't want to spend time solving computer problems / be an early adopter. I want my computer to work so I'm still sticking to 32 bit. The next PC will probably get a 64 bit Linux install but that is a few years away.

[VulcanBB18]

What does the BIOS report the memory size as?

Windows 10 will read the DIMM to get the information about what size they *should* be, but the actual memory size reported as being used is determined from the BIOS.  If the BIOS has decided that some of the RAM is bad or one DIMM doesn't pass POST then you'll get wacky memory size reported in Windows.  Even more so if there aren't correct drivers loaded for the motherboard chipset in Windows.

cheers,

[Monkeh]

What does the BIOS report the memory size as?

Windows 10 will read the DIMM to get the information about what size they *should* be, but the actual memory size reported as being used is determined from the BIOS.  If the BIOS has decided that some of the RAM is bad or one DIMM doesn't pass POST then you'll get wacky memory size reported in Windows.  Even more so if there aren't correct drivers loaded for the motherboard chipset in Windows.

cheers,

Err.. no, OSes as a general rule don't use SPD data for this.

It's a 32-bit install. This is what happens. Please no out of the box theories to confuse matters.

[amyk]

It's funny how many people propagate the myth "you can't use more than 4GB of RAM on 32-bit Windows" because it's what Microsoft officially say and they like to refer to 2^32 = 4GB (it's actually 36 bits of physical address space with PAE on), but just like with scope bandwidths and options, it's an artificial limit you can unlock...

http://www.geoffchappell.com/notes/windows/license/memory.htm

[wraper]

What does the BIOS report the memory size as?

Windows 10 will read the DIMM to get the information about what size they *should* be, but the actual memory size reported as being used is determined from the BIOS.  If the BIOS has decided that some of the RAM is bad or one DIMM doesn't pass POST then you'll get wacky memory size reported in Windows.  Even more so if there aren't correct drivers loaded for the motherboard chipset in Windows.

cheers,

Err.. no, OSes as a general rule don't use SPD data for this.

It's a 32-bit install. This is what happens. Please no out of the box theories to confuse matters.

Although it's apparent that the main issue here is 32 bit os, I can say something form my experience. When I tried 4x 16GB ddr4 ECC unbuffered sticks on certain ryzen motherboard, win 10 x64 would show me full 64GB present but only 32 GB available and the rest of it showing as "hardware reserved". After long fighting, it turned out motherboard didn't like one particular stick when another stick is used on the same channel, although it appeared fine in bios settings. But this stick worked completely fine when left alone in the channel. So I replaced that particular RAM stick with another one and I no longer had 32GB reserved issue. Out of that I can conclude that Win 10 had a way to detect how many sticks there actually were, even though half of them were inactive.

[bd139]

32-bit address space is not an artificial limit. Extending that with PAE is a hack job akin to HIMEM.SYS from DOS days. It's a stupid solution and should never be used. It's like building a shed on the back of your house. Every time you fill your house up, you have to go back and forth to the shed to reorganise stuff. Answer is buy a bigger house.

LME incapable or buggy as fuck drivers which I've encountered: FC cards, PCI serial cards, Matrox graphics cards, virtualization drivers (vmware workstation).

Also note that drivers which aren't compiled with LME actually have to copy memory twice in and out of the address space of the CPU so you get shitty performance.

Also even if you have PAE enabled, if hardware takes memory away, then that's taking it out of the 32-bit address space of the CPU, not from the total PAE allocated space.

Just use a 64-bit OS. There's no reason not to, unless you have some weird driver which is 32-bit only or something at which point you should start thinking about replacing that hardware.

[Monkeh]

It's funny how many people propagate the myth "you can't use more than 4GB of RAM on 32-bit Windows" because it's what Microsoft officially say and they like to refer to 2^32 = 4GB (it's actually 36 bits of physical address space with PAE on), but just like with scope bandwidths and options, it's an artificial limit you can unlock...

Some editions of Windows 2000, as well as other server versions, do not have the same hobbling applied. Desktop versions, on the other hand.. No myth being perpetuated here.

Although it's apparent that the main issue here is 32 bit os, I can say something form my experience. When I tried 4x 16GB ddr4 ECC unbuffered sticks on certain ryzen motherboard, win 10 x64 would show me full 64GB present but only 32 GB available and the rest of it showing as "hardware reserved". After long fighting, it turned out motherboard didn't like one particular stick when another stick is used on the same channel, although it appeared fine in bios settings. But this stick worked completely fine when left alone in the channel. So I replaced that particular RAM stick with another one and I no longer had 32GB reserved issue. Out of that I can conclude that Win 10 had a way to detect how many sticks there actually were, even though half of them were inactive.

It's entirely likely the BIOS still reported the full amount of RAM and left an area marked as reserved. They could be checking the SPD, I admit - but it's immaterial whether they do or do not, because you do as the BIOS/UEFI tells you or things explode.

[wraper]

It's entirely likely the BIOS still reported the full amount of RAM and left an area marked as reserved. They could be checking the SPD, I admit - but it's immaterial whether they do or do not, because you do as the BIOS/UEFI tells you or things explode.

What I mean is as OP got 1.7 GB available, things may be more complicated as just 32 bit OS. Probably he had it like 2GB detected out of which 256 - 320 MB were used for iGPU.