I've got close to that. I looked at their score, and didn't realize they shwed the gpu and cpu score. So I get my cpu score close to theirs, and bench again, this time with my card at 735/1060.

I got 7121 marks on my gpu score
They got 7890 marks on their 4870 gpu score

My cpu score was 13295
Their cpu score was 13132

I noticed that cpu speed does not affect the gpu score at all (My gpu score was exactly identical at 3.6ghz and 3.8ghz.)....

Overall, I got 8050 marks
They got 8769

My gpu score jumped more than 100 marks by increasing the gpu frequency 15mhz (and memory 10mhz). At 750/1050 this card should score around 7250 gpu marks which would bring it close to the 4870.

I am guessing that this card clocked at 800/1200 should EASILY overtake the 4870. I'll try that when I get the right size variable resistors.