Is 1080p "too much" for Live TV on the Pi?

[2twisty]

I can't run my Pi in turbo. It crashes too easily. I can't even run it in "Hi." I even tried a 2.1A power supply from my wife's iPad. Nope.

I was stuck at "medium." I did bump it a bit over Medium and it seems to be stable.

Here's my settings:

arm_freq=950
core_freq=400
sdram_freq=450
over_voltage=1

Anyway, even with these settings, I can't reliably run everything in 1080p. Videos play fine, but Live TV from MediaPortal is just too CPU-intensive on HD channels. I get too much stuttering and re-buffering.

So, I dropped everything to 720p. The GUI res, the Video Output, everything. Now I've got stable LiveTV Performance.

Aside from pushing the envelope with overclocking, is there anything else that can be done to improve LiveTV Performance in 1080p? Since my videos that are 1080p play fine, I'd like to be able to play them in their max resolution, but not at the expense of having unwatchable LiveTV.

Ideas?