Please help with BMI Pro computer setup

Hey everyone!

First let me say I am completely ignorant with computer hardware. I don't know much beyond the basics.

I have a computer setup (specs below) for recording xbox. It uses a Black Magic Intensity Pro.

When I try to record in Motion JPEG I get a lot of dropped frames. When I record uncompressed it usually records perfectly, sometimes it drops a chunk of frames. When recording in Motion JPEG the faster / more action on the screen the worse it drops frames.

Is my computer simply just not powerful enough? Maybe I need a better graphics card or power supply?

Thanks in advance. Love the forum!

HP xw9300
WIN XP PRO 64
AMD Opteron Processor 252 (2 CPUs), ~2.6ghz
10240MB RAM
NVIDIA Quadro FX 3400/4400 256MB - Chip Type Quadro 3400