question about how it works

[adamrussell]

Ive had a few glitches and was trying memtest out. So far everything is passing. But since Ive had this computer Ive suspected that memory might not be right when usage goes much over 50% and I wonder if memtest would even see that. As I watch it run it seems like it tests a only word of memory at a time, so it may not actually test what happens if most of the 8GB is in usage at the same time. Am I wrong about this? Please educate me.
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edit: the reason I have suspected large memory usage problems is that I have had a few times when a windows popup comes up telling me Im running out of memory and to shut down a program. But task manager says Im only up to 60% memory usage. Then the other day there was a blue screen. Bad_Pool_Header

[David (PassMark)]

The memory management system in Windows is complex. Very complex. It can't be explained in detail in a forum post.

Instead I suggest you read some of the information on the Microsoft web site,
http://support.microsoft.com/kb/2160852
http://msdn.microsoft.com/en-us/libr...(v=vs.85).aspx

The Windows Internals book is also a excellent reference.
http://technet.microsoft.com/en-au/s.../bb963901.aspx

If you have a hardware fault in your RAM, then Memtest86 should pick it up.

If you have some other issue, like running out of RAM in Windows, then Memtest86 won't help at all.

[orioon]

Exploit mitigation techniques makes this even more complicated.
http://en.wikipedia.org/wiki/Address...rosoft_Windows

Which OS is the machine running on?
Just because Windows has more than 50% RAM usage doesn't mean that it uses all this memory, it only references the allocated memory.

You won't see some memory consumptions in the task manager though.
RAMMap will help a bit, but it can be very difficult in some cases.
Definately give the Windows Internals book a read which David already referenced.
Also have a look at MArk Russinovich's Blog, he has some similar cases which might help you.
http://blogs.technet.com/b/markrussinovich/