[12.3 x86_64] out of memory/RAM fragmentation

Hello all, after installing suse 12.3 64bit I went into a number of problems and have solved them all but one.

I regularly run Thunderbird, Firefox with 5-10 tabs (including flash content), shell, mc, image viewer, Eclipse, Amarok, Blender3D, etc... all at the same time...
Now fun comes, when I close some of them or all of them and try to open something else, it just wont start sometimes giving a simple error popup (could not start). After that even the recently closed applications cannot start giving the same error.

I have 8Gig of physical RAM installed checked periodically with memtest and no errors found. My swap partition is ~4Gigs. Programs like free, top, htop, Kinfocenter, etc report in all combinations of programs run that I have 99-96% swap free, Application RAM usage 30-45%, Disk cache the rest of free ram minus 2-20% (as expected). When Free Physical memory goes below 1% that is when problems start.

I close all programs i can and run
My free physical ram goes up to 80-85% but I cant run anything :( ....
I have to Log out and log back in again to make things work again....
It happens with KDE4 (v4.10.5 r1) and with Xfce (v4.10)... I run only the bare minimum plasmoids

Last time I had similar issues was with my Amiga Chip RAM fragmentation.....

My system and repos are uptodate
I have 2 ATI cards HD5xxx (proprietary drivers) with 3 monitors attached (left is screen 1, center and right is screen 0 with one big desktop)

Please help me find the leak here!...