Weird RAM usage problem with XP. Please help.

I own a laptop running XP Professional Media Center Edition with 1015 installed RAM. Just recently I have started having interesting problems with RAM usage.

I am using FreeRAM XP Pro to monitor memory usage. This is the weird problem I started having. When my computer starts and all the programs load, I usually have between 585-600 MB of free RAM. Let's say I launch Firefox. The RAM usually goes down to the 500-520 range. Before this problem, if I did not launch any other instances of Firefox, the RAM would hover in that range. But now, after about 5 minutes (without launching any new programs, just having Firefox open) the available starts rapidly dropping to about 330 MB. If I check the Task Manager, I notice that many programs and services have now bloated to about 2x their initial memory usage. I am fairly certain that this DID NOT happen before.

Does anyone know why this is happening? It certainly does not seem normal to me. And small problems with XP usually turn into large ones in my experience, so I am pretty concerned. And I do not think that the problem is not the FreeRAM XP Pro software, as I have used it since long before this problem showed up.

 

I'm also using XP Pro and FreeRam XP Pro on a laptop. Initially it had 1 gigabyte of RAM installed, with about 320 megs of RAM used on bootup, with all programs running that I need to safely access the net (and MG, first port of call, of course).

Yesterday I added another 256megs of RAM (now 1.256 gigs) and RAM used has increased to around 400 megs, with no additional programs loaded by me. I had another problem so the shop may have loaded something else to startup, but I haven't fully checked this out, as yet.

What I am long windedly getting at, is what is the best program to check how much RAM is actually being used by what programs.
I don't mean processes, services or startup as I have them well covered.
I mean how much RAM is each of the svchost.exe processes actually using, for example

If someone can suggest a program it may throw light on both of our queries.
Sorry to slightly hijack this post. Bazza

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