XP 32bit and 4GB of mem? Can only use 3GB? You CAN use that wasted 1GB!!!

I have a couple of PC's with 4GB RAM dual booting XP 32bit. Of course, XP 32bit only sees 3GB as the vid card uses up the other 1GB address space.

Well, I've just found out you can do a neat trick. Some RAMDISK software is capable of initiating its own kernal memory management in XP 32bit (not all do this), and uses that wasted 1GB for - an Amiga style RAMDISK!!!

I've not tried it yet, but there are free and commercial solutions. Here are a couple I found:

http://www.knowledgesutra.com/forums...-in-xp-32bits/
http://www.jensscheffler.de/using-ga...k-in-windows-7
http://www.superspeed.com/desktop/ramdisk.php (read about "extended memory access)

The idea of a 1GB RAMDISK in XP 32-bit on a machine with 4GB RAM sounds awesome. Imagine what you can use it for - temp folder, cache folder, various XP shell folders (like those containing index.dat files), SWAP file (kind of pointless) - but at least it gets used for something. There may be a small performance hit from using PAE feature in XP 32bit, but it will be very small and nothing really on a dual core or above CPU.

May not work, but I'll try it out soon and if anyone else gets a chance or is interested post back here. :)

Nice find. It definitely is annoying using a 32bit OS with 3GB+ of ram and losing some of it.

I look forward to finding out if you get it to work. :)

Tried this out and it works. :)

Some notes -

PAE (Physical Address Extension) is often already enabled by default in XP SP2 SP3 and CPU's capable of hardware DEP (Data Execution Prevention). DEP requires PAE, so don't bother adding the "/pae" switch to "boot.ini" as described in the links. A quick way to see is System Properties (My Computer->Right Click->Properties) - it will say "Physical Address Extension" where it lists CPU model and speed.

The RAMDISK pack you need is "Gavotte_RAMDisk_1.0.4096.5_200811130" (search Google) - not sure if a newer version is available, seems like a forum private project.

EDIT: Found original forum project thread (Google translated) - http://translate.google.com/translat...906641&act=url

1. All you need to do is add the registry entry (double click ram4g.reg) which adds a single entry telling the RAMDISK to use PAE mode (check what it adds in notepad).
2. Then run the ramdisk.exe program, and click install. This installs the kernal driver. It also has a remove button.
3. Don't change any settings - just exit using the window's X. It will automatically use the mem you have sitting around unused and mount a RAMDISK using the letter R: , formatted with FAT32. It will be labelled RamDisk-PAE. :)

From my testing - if you did change settings and click apply and ok (no need to as outlined above), as long as you've selected a size smaller than your missing mem (default 16MB) it won't make a difference. It will still end up 768MB with the registry addition telling it to use PAE. If you select a larger size (like 1GB+), it will eat into your normal windows mem (3.25GB area) by the amount you are over. You can change these settings on the fly - the driver reformats the disk automatically and adds a Temp dir.

Also, the remove button also removes the registry addition added by ram4g.reg as well as the kernal driver it seems. So if you remove it and want to re-install, remember to add the ram4g.reg entry or it will not use the missing mem via PAE. I discovered this whilst re-installing and ended up with the default 16MB RAMDISK using part of the 3.25GB area. It looks like the author cleans up after himself. :)

As for the other options, fixed disk works best as it allows the RAMDISK to work as a hard disk as far as Windows is concerned which gives it more flexibility and less limitations.

So it seems to work. I haven't given it a thorough test, but it looks to be using my missing ram. In XP 32bit, I can normally see 3.25GB in Task Manager. The RAMDISK driver made a disk 768MB in size using PAE mode with no impact shown on my 3.25GB main memory.

Great news. The biggest use I can think of for this is compression and decompression processing as the ram disk will be much faster for the system to access. Especially useful for multipart downloads you want to recombine into an ISO. And the resulting ISO can be held on the ram disk for burning to disc, and then deleted without ever touching a real hd. :)

Good uses I agree. I too can also think of some good uses - just like an Amiga RAMDISK. :)

It's so simple and quick to install. Doesn't even need a system restart. What I need to test is stability and if it affects normal performance in anyway.

So far so good however. I'm just happy to make use of that mem which was missing in XP 32bit. Admittedly, I use Win 7 mainly these days but I do have a HTPC using Win32 and 4GB mem, plus a XP install dual booting with 7 for older games and apps.

Have you tried XP Mode in Win7? I've got that installed for both my Win7 64bit PCs and it works well. It is only really VirtualPC and a copy of XP running in a virtual machine, integrated into the Win7 desktop, but its done quite well. I've actually had no need for XP since moving to Win7 as everything I've wanted to run I've managed to get working, even fairly old games like GP4.

But my emulation PC is still running XP SP3 as some older emulators don't like anything newer and all emulators still support it. But that only has 3GB ram so isn't a problem. Although, saying that, I have started running some emulators on my main PC. I gave Zinc a try the other day and it was brilliant. Ran everything in high res at 60fps with no slowdown or stuttering. When I originally ran Zinc when it came out on an AMD64 is was managing around 30-40fps and wasn't fully playable. Great to see the arcade originals of games like Soul Edge and Tekken 3 running perfectly. :) ... Sorry for going off topic.

This patch is pretty useless for you then, if your XP machine has 3GB. Very useful to me however. :D

Yes I've got XP mode running in Win7 Pro 64bit and it's useful for apps - virtual pc is also good for testing linux - but I have some software that just requires XP 32bit, especially some of my older 3D accelerated games and as you mentioned emulators.

Plus I can run Perfect Disk defrag (I only have the older version for XP) on my Windows 7 partition and scan it for viruses using Avast from within XP. Also Avast's boot time scan only works in 32bit Windows.

Finally I just love XP - it's an OS that's been around for nearly 10 years - have it set up perfectly and it's hard giving that up! Dual booting is fun and you have a back up OS.

As for Zinc, I've never heard of it before so can't comment. Will have a look however. By the sounds of it, all of the emulation is still CPU driven. Shame they can't get some GPU acceleration for those with slower CPU's. Nice to hear those classics now fly however. :)

As for off-topic, I too will indulge. When I edit posts, I have to go to the advanced edit. If I use the first edit screen, all I get is a spinning circle when I try to save. So I then have to click advanced edit, then save changes and it works. Is it a know forum bug?

I'm using Firefox - might be an addon I have, like Flashblock, Download Helper, Cookiemonster or Betterprivacy.

Originally Posted by Bloodwych:
When I edit posts, I have to go to the advanced edit. If I use the first edit screen, all I get is a spinning circle when I try to save. So I then have to click advanced edit, then save changes and it works. Is it a know forum bug?

We had a discussion about that here, but the problem still exists, is a bit annoying, because you don't remember all the time to go advanced, and then you get stuck on with the spinning circle.

Thanks Demon Cleaner - also noticed how many game Hiscores Submeg has!!!!! It breaks the forum!!! :blink: :lol:

I'm also blind - it's clearly stated under forum bugs on the main news page. Doh!