Okay scratch the enhanced questions, I checked your results and you are doing the mix too. You are averaging the same processing time for the standard units as me (about 7,000 to 8,000 sec) but I have a slight edge on you with the enhanced units: my range is 16,000 to 33,000 sec with most of them being at the 21,000 mark whereas yours is more like 19,000 to 35,000. It seems to me that your Sempron is not much slower than one core of my CPU.
My higher average credit comes down to a 2 cores vs 1 performance difference (unless I have calculated wrong)
Edit: just saw that some of those results of yours for standard units were 14,000 so the Sempron is definitely slower.