Worth it to OC onboard video?

[Dida]

I recently threw together an ultra low-end HTPC using Sempron 145 (2.8 GHz single core) and AMD 880 based HD 4250 onboard video chipset. To my dismay, when playing 1080p contents, the CPU usage would often hit 100% and sometimes the video stutters. I knew this HTPC is low-end stuff, but expected it to handle 1080p in VLC. (Would Blu-ray movies be more or less demanding? Even a low-end HTPC could not possibly be weaker than a $100 Blu-ray player).
I OC'ed the CPU to 3.5 GHz, now thinking about squeezing some juice out of the HD 4250 as well. Is it worth it?

 

[Zelig]

Are you using GPU acceleration?

If you're not using GPU acceleration, the video card is going to make no difference.