It takes a lot of research to find them, but there are actually quite a few cheap quad core systems out there, such as the UDOO. ODROID will be supposedly be getting the next-gen 8 core smartphone processors in the next year or so. I don't mean to be off-topic, I just remembered that fun fact.
Here is the standard ARM Linux OpenCV instructions, which is a little confusing if you don't use Linux, but the people in the
OpenCV forum are really nice and know what they're doing :P
Here is something I found on Pandaboard specifically. Cheers!