RAM not completely usable!

[Hercules2905]

Recently, I upgraded my Dell Inspiron 15 3521's memory from 4GB to 8GB by adding another stick of RAM. My PC, Speccy and BIOS all detect this new RAM but the Properties tab shows only 2.38GB is usable. This is a big problem because that is less than what I used to get before upgrading the RAM. Earlier with 4gigs of RAM, 3.87 was usable but now with 8gigs available, only 2.87 are usable.
Any Suggestions please.

P.S. I have already tried removing the memory limit in msconfig.
P.P.S. I also have 64-bit Windows installed so that's out of the way.

 

[James Mason]

Start > Search > "Resource Monitor" > Memory tab > how much memory is hardware reserved?

Did you just buy another 4gb stick? is it the EXACT same model as your previous stick?

 

[Hercules2905]

Scrap that! It just automatically detected the RAM after switching the RAM slots and now it says 7.87GB available. Surprisingly, the two RAM sticks arent the same and one of them had 16 black blocks and the other 8....anyways it is working now and thanks for helping out! I'm sorry if I might have wasted your time at this stupid question of mine. Thanks a ton!