16GB of RAM for Photoshop or will 8GB be ok?

[Hunders]

Hi guys.

Currently I have 4GB and my RAM gets blasted and slows my PC right down when using PS so I want to upgrade but I'm wondering if 16GB would be wasted and that perhaps 8GB is the better option?

Can anyone advise please?

 

[Hunders]

I have 64 bit Win 7 and I'll typically be editing 20MB RAW files from my camera.

 

[Hunders]

Ok cool, 16GB it is then! I will get 4x4GB as my motherboard only supports 16GB so an upgrade to 32GB wouldn't be possible.

An SSD would be nice but I don't like the price per GB for them at the moment.

Cheers.