Please give me any advice as I know I will have to upgrade the MB, and with that the CPU as well. Been looking at CPU Benchmarks and noticed the old 64 X2 6400+ is lagging way behind, but for what I need, might be enough. Anything not used will be sold to pay for the new parts.
You could capture and record 4 video streams (with a second tuner) while playing Battlefield3 if you wish. A 960T should do quite nicely for a power user. Or, you could simply go low-volt with a AthlonII 240. Here's a 240 at 4x240MHz - 42% CPU, 0.09v, capturing and recording the stream: