Today I booted my computer and it was hell slow and when I clicked computer properties then it showd me that only 256 mb of ram is useable but I have 4GB ram installed !!
Please help me , I cant use my computer .
I have heard of instances similiar to yours and have a few reasons why your compouter might be doing this. One reason might be that the contacts for your ram cards are some what dirty, causing a bad connection between it and the motherboard. Another reason may be that your RAM cards died, leaving you with 1 working one. Still another reason may be that Microsoft Windows has a corrupt registry entry causing your computer to incorrectly use your ram. My bet is that your Ram cards are either dirty, or dead. Try using Memtest86. You can download it at Memtest86.com - Memory Diagnostic. Try that first. If you don't want to try that program and are currently running Windows Vista or Windows 7, you can try using the built in Windows Memory Diagnostic. The standard memory test will be performed, but you can press F1 and change it to advanced. Let it run and don’t do anything else. Finally, if you have determined that there is a problem with the memory on your computer, you can try removing the memory one by one to see which one is causing the problem. That means you need to open your computer and take out the ram cards and rerun the diagnostics tool. Don't toch anything inside the computer while it is running, trust me, I speak from experience. It might be better yet to put the cover back on when you when you go to test the ram. If you don't know what a ram card looks like you can search it on google images.
I forgot say that inorder to get at the built in diagnostics tool, you need to press F8 while booting Windows. If that doesn't work, try some of the other F keys because my is F12, not F8 so it may differ for different computers. Here is an image of what it should look like.
and btw. yesterday i did something msconfig , I changed the proccesors from 1 to 2 and after that it did that
and now It dosent even show that I have 2 proccessors but I have amd athlon dual core
And I run win7 but I think I will downgrade to xp