Windows 7: High RAM usage

I have been getting this weird problem lately with Windows 7, and I apologize if this has been posted and solved before, but I couldn't find anything. So, I don't remember when this started, but my RAM usage is upwards to 78% with 4 GB of RAM. And I am currently running a lot of programs, true, but closing them all does nothing. It's as if Windows is failing to eliminate the resources used by the programs even after closing. The RAM is around 48% on startup (which seems insanely high...), and as I open programs, it increases until I get only 200 MB or so left. And it won't go way all that much even if I end every process I can. Anybody have any clues to fixing this? It never happened when I was running XP on the same machine. MY thoughts on it is that one: there is a hidden process or program that isn't showing and is always running and eating up my RAM; and/or two: Windows isn't utilizing the RAM like it should be. 4 GB is over-kill if I was to leave it as-is on startup. But it eats it away like nothing. Help? Thank you.

You are (most likely) observing the new method of memory management. Windows is caching to RAM - all of which will be gracefully released when needed. Can you post a snip of your Task Manager performance window for confirmation?

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I believe the way to test this is to load different programs and see if memory is made available. Windows keeps a lot in the cache, but should release ram immediately when necessary.

What you are seeing is indeed normal. Rather than have RAM sit around empty and unused, Windows preloads stuff into RAM that you often run so that it opens quicker when you need it. The thing is, when an application needs RAM, Windows will simply overwrite that cached content...so you really have nothing to lose. The way I look at it, if I have 8GB of RAM...might as well use close to 8GB of RAM. No sense in always having 6GB of RAM just sitting there unused.

Well, it does not seem like Windows is doing that. Like when I am running with 200 MB of RAM left and run any programs, it takes foreverrrr, compared to when I just start it up. And the RAM will keep adding up more and more.

Edit: Another thing I forgot to mention. When shutting down, even after closing everything before-hand and ending all processes that I can (as a test), it tells me that Windows is waiting for a program to end so it can shut down, but in the list where it shows the programs, there is nothing. Which leads me to believe it's not a program, but either a service or hidden process or something like that. I could be wrong though.

Thank you VERY much for your fast responses. ^_^

Attached are the images of Task Managers Performance tab.

Running any security software, anti-virus, anti-malware etc? Because it is not Windows itself that is doing it, but either a driver or another process that has a memory leak.

Just avast!, other than that... no. I've closed that program as well though. Nothing seems to reduce it past 70%. No matter what I close.

Download ProcessExplorer (Google it, should find a link on Microsoft site).

Once downloaded, run it as administrator, and right click on the column bar with all the column headers and click "Select Columns". Click the Process Memory tab and select Private Bytes, then click "Ok" and sort this colum in ascending order. It shows a lot more processes than task manager.

I had this problem and fixed it today. Mine was caused by WMP network service, the sharing service for it. After stopping this service and ending the process in ProcessExplorer, it fixed all high RAM usage.

I already have that downloaded! Haha, well, I already used it to find something with high RAM usage, but nothing shows above 225,000 K (about). So I really don't know. The only thing related to your problem was wpmntwrk.exe which could not be killed. =/

Disable the service.