I just thought that I would play around with bitcoin mining.

I have an idle system (Intel Core i7 3930K (6-core, 3.2 GHz stock, OC'd to 4.5 GHz, EIST enabled, HTT enabled, C1E enabled) on Asus X79 Sabertooth, with 8x 8 GB Crucial Ballistix DDR3-1600 RAM, Windows 7 x64 Professional, EVGA GTX660 Superclock)

I installed the GUI found here: http://bitcointalk.org/index.php?topic=3878.0

and I also downloaded the 0.8.1 bitcoin client so it got my wallet set up already.

I was able to start the GPU mining ok, but I had a hard time trying to get the CPU mining going.

It was looking for the miners/ufasoft (which I couldn't find in the directory where I un7zipped the GUI so I downloaded ufasoft separately and installed it and tried to point the GUIminer to that executable, but it still didn't work. So I'm not really sure what's wrong with it.

And so far, it was fluctuating between 70.7-71.3 MH/s so I'm not sure if that's a good number for the hardware that I'm running.

I have read that nVidia GPUs aren't very good for bitcoin mining, but the system was originally built for something else entirely (engineering simulations, more specifically FEA and CFD).

For nVidia GPUs, does it matter if I'm using the OpenCL miner or the CUDA miner (through GUIminer) or is that more of a hardware limitation, regardless of which GPU language it is running?

I've already read through those guides and it doesn't really help to answer these specific questions.

BTW...downloading the entire block transaction history with the original Bitcoin cilent (Bitcoin-qt) takes a REALLY long time. I would have thought that with it running on a peer-to-peer network that it would have been a LOTTTT faster.

Help or suggestions or ideas would be greatly appreciated (but I'm not at my system right now, so I might not be able to actually try them out for a little while). Thank you all in advance.