1 x 1 Gig or 2 x 512 MB RAM?

I have a MBP Core Duo with a gig RAM and would like to upgrade to 2. How can I tell if it has 1 x 1 Gig stick or 2 x 512 MB sticks?

G'day Doc!

Go to the Blue Apple Icon (in Finder press Ctrl+F2) and scroll to About This Mac. Then in the window that appears, click on More Info... Then a new window opens ... actually it's the System Profiler. Scroll down the left pane until you see Memory and click on it. In the right section look at the top window and it will describe your insalled RAM.

Thanks!

BANK 1/DIMM1:

Size: 1 GB
Type: DDR2 SDRAM
Speed: 667 MHz
Status: OK

Click to expand...

Are there two banks then and one has a gig in?

This is mine for comparison:

BANK 0/DIMM0 ... Size 1 GB - Type ...DDR2 SDRAMM
BANK 1/DIMM1 ... Size 1 GB - Type ...DDR2 SDRAMM

Click to expand...

I have 2 X 1GB RAM installed.

Your post show what's installed in BANK 1, I presume there's no BANK 0?

If not then you have 1 X 1GB RAM installed, Doc ....