I know a lot of people say you need a decent amount of memory for scrypt mining but I still don't understand why. If I look in taskmgr I see cgminer taking up ~55MB. I am using two 290's. Thoughts?
A lot of people are clueless. I have 5x 290s per mobo with 4GB of ram, and never had an issue. 2GB of ram should be more then enough for a linux miner. That said, the distros like bamt are messed and seem to eat RAM, but my gentoo installs have 90% free memory no matter how many cards are installed.
The Asrock BTC boards will run 5 or 6 R9 290s no problem.
With less than 3-4GB or a 32bit OS, you can run into issues - "Error -5: Enqueueing kernel onto command queue" when attempting to start cgminer.
There are brief periods of large memory allocations and CPU for the Xorg and cgminer processes.
I saw this when I built a 6x rig and was using 2GB of RAM since its what I had laying around. With 2GB, all sorts of issues. With 4GB, no problem.
I agree with the new cards I had to have 8GB of RAM with 2 Cards or CGMiner would crash with the enumerating kernal error. On your Multi card Rigs are you using regular CGMiner 3.7.2?