high processor usage by cinnamon

[romleinster]

i'm running mint 14 on an amd a6-5400k, vesa graphics: dvst and 7.3 GB of ram.
When idle, top gives acceptable but high load avgs (around 0.4 for 15 min). As soon as I run a process though (like a video in firefox), loads get very high (well above 1.0 for the 1 minute) and stay high. During this time, cinnamon is using the cpu about 90+% of the time.
this doesn't happen when using a gnome classic session. Anyone else having this issue or know of any fixes?
Thanks

[mank_in]

Are you are using cinnamon 2D
cinnamon 2d using llvmpipe software rendering, cpu take all video rendering.

[romleinster]

nope, i've been using the 'regular' cinnamon with vesa, not lvmpipe.

[mank_in]

what the output of :

Code: Select all

inxi -Gx