4gb ram but only 3.25 usable

[vatz]

i got some new ram (4gb Corsair Dominator DDR2 PC2-8500 (1066), 240 Pin) and now it says only 3.25 is useable. my system spec is in my profile. any ideas?

 

[Jonathan_King]

That is because you have the 32-bit version of Windows. Due to technical limitations, 32-bit can only address up to 4GB, but in practice, this number is lower. Upgrade to the 64-bit version and you will have access to all 4GB.