OK - i did the opposite of what i said. I replaced the 9400GT(MSI) with a Gigabyte GT220 1GB DDR3 - with a big 80mm fan. A quick google and i realized i would loose my hdmi audio
and i need the 190.53 driver - i added the avernard repo and upgraded everything and 190.53 nvidia driver. Hard to believe but everything worked perfectly and i'm pleased to report NO MORE BLOCKS !!!!
. The GT220 has better power control as my 9400 had none. I use VDPAU HighQulity setting in myth. All mpeg2 channels look amazing. a bluray i have (IceAge3) played back with only around 12-15% cpu . It is a merry christmas.