problem with RAM

[Mike4c]

I just installed 24 GB off RAM but only 16 GB is useable .Did i miss some thing ? I reinstalled them four times, to make sure them were making good contact.

[Tradesman]

It's your OS - Win 7 Home Premium tops out at 16GB of DRAM, to use more you'll need Win7 Professional, Enterprise or Ultimate

[Mike4c]

OK thanks,Will photoshop use it all ??Do I have to up grade windows ?

[Tradesman]

For most folks, No. Depends on what your doing, the quality of the image (depth/size) etc. If you have multiple images open that are of very high quality, you can eat up some DRAM. For most 16GB is sufficient