startup problem

Hello I got the new 2.0 mac mini and I installed 4 gigs in it, 2 2gig modules from Otherworld a few days ago...and it took fine, and I was able to see the full 4gigs and it started fine several times. But for some reason after installing the rowmote helper app that goes along with the rowmote iphone app, it asked to restart so I did but when I did the apple menu came up, then sorta hung for awhile, then the apple icon switched to a circle with a diagonal through the circle. I tried the SMU/PMU reset but that doesnt help. Is it a drive problem? Or could it be the ram I installed recently?