Lots of problems regarding Refrenced Memory.

Recently My computer has been crashing alot. I mean i havent downloaded anything. Its been the same since i can remember but now i get lots of errors. When i extract a file with WinRAR i later get a memory error, When running a setup.exe i get a refrenced memory error.

If anyone can help it'll be greatly appreciated.
Ps. I did not yet Install Sp2.

Also i have 512 ram.

 

well i dont know if anything specific is causing you trouble or not. right click my computer>properties>advanced and then check the setting for virtual memory. it should be twice the size of the RAM. Also i use a cool piece of freeware called HARE ( http://www.dachshundsoftware.com ) which made my computer faster. you can try that

 

thanks. will check