I have 32bit Windows 7 with 4Gigs RAM, and also use the 3gig switch, I let Windows manage my virtual memory settings, It’s created pagefile.sys in the root of Drive C, and it likes to set it up at a fixed 3.7GIG. (Well it never gets bigger or smaller), yet I appear to run out of RAM if i’m heavy gaming, etc. (Crashes, overflow errors, etc). Every time I chk the pagefile.sys it appears it hasn’t been modified or accessed since I last changed the virtual settings(Right now its on the 30/4/2013 23:33 and the modified or accessed date never changes and that’s now 2 days ago), even if I manage virtual settings myself and create a fixed size, it will create a new pagefile.sys on a reboot but it will never appear to touch it again, so i’m feeling I’m just stuck with only the RAM installed in my PC, and if I run out, windows won’t write to my pagefile.sys. Any ideas, can I test a way to see if Windows is writing to my pagefile, it doesn’t appear to be touched, and there’s no pagefile.sys on any other drive because I only got one drive. Note: I have 119Gig free space of 246.1Gig also if that’s relevant.
1. Get rid of the 3GB switch (actually called extenduserva now), unless your games actually tell you to use it. It refers to virtual address space, not RAM (well, it sort of influences RAM usage, but only very indirectly). It constrains the OS to just 1 GB of virtual address space. That’s usually a bad thing. Most programs are not built in such a way as to be able to take advantage of this option anyway (they have to be built with the largeaddressaware flag). But the extenduserva option constrains the OS’s use of v.a.s. even if no process you’re running can take advantage of it!
2. The pagefile accessed date does not change to reflect paging IO. The pagefile is not read or written through normal file access paths.
3. To see if you’re really running out of RAM, check Task Manager’s “Performance” tab. As long as “available” is more than 100 or 200 MB, you’re ok, unless you’re running programs with very “spiky” demands on memory. Ignore the “Free” counter as Windows opportunistically uses “Free” memory to cache stuff it thinks you might need – but that RAM is still immediately “Available” for other uses. Hence the “Available” counter is the most interesting.
n.b.: It’s Windows’ job to “worry” about RAM usage. You really don’t have to. In particular, basing your “worry” threshold on a percentage of total RAM doesn’t make a lot of sense if you think about it. You want to have 30% RAM free? Why would you want around 1 GB of free RAM? Free RAM is wasted RAM.
4. To check actual pagefile utilization, go to a Run prompt or Command prompt and type “perfmon”
Click “Performance monitor” in the tree in the left pane
Click the big green plus sign (+) (It means “add counters to chart”)
In the upper left selection box, Find “paging file”, click the down-pointing arrow to the right of the words “Paging file”, and click “% usage” to select that counter
In the “Instances of selected object” box, click the pagefile you want to watch
Click the “Add” button (this adds the selected counter(s) to the “Added counters” list)
Click OK
Watch the graph.
You can set up PerfMon to log this data to a file, say while you’re running your game, which you can “play back” later. There are several hundred other counters too. For example, if you want to know if a process really needs that “3 GB” option: Start the process, then go to PerfMon. Select the Process object, then in the “Instances” box, select the process you want to watch. The counter you want is “Virtual Bytes”. If this never exceeds 2 GB then the process is not approaching the 2 GB per-process limit on virtual address space.
Crashes and “overflow errors” are usually not a sign that you’re running out of RAM. (Usually you will get pop-up messages like “the system is running low on virtual memory” at such times.) Your symptoms sound more like your CPU is overheating.
What makes you think ram is causing the crashes rather than crappy graphics hardware?