Upgrading RAM on iMac Late 09

I have a late 2009 iMac, 21.5", 3.06ghz intel core 2 duo with a measly 4 GB 1067 Mhz DDR3 ram (i bought it used a few years ago for like $250). As you can guess, processes are very bogged down.

Anyway, i'm on MacSales.com wanting to upgrade my RAM with some OWC chips. I was wondering if it would be better to upgrade all 4 memory slots (4 gb each) for a total of 16 gb memory, which is the limit for this model--or if I should just go with two 4gb for the two open slots i have available. I suppose what i'm asking is if it will really make a huge difference in tasks from 12 gb to 16...

Thanks

It will handle up to 16GB, which will be 4x4GB from Crucial or Owc.

The biggest band for your buck will be a Solid State Drive if you are adventurous enough to do the job yourself. Go over to ifixit.com and look at their tear down for that model.

And rememberGoogle is your friend!

Just did this with my late 2009 iMac today. Ordered 2x4GB Corsair chips and installed them to total 12GB with fantastic results. Do it, you'll love it.