I'm also interested in a benchmark of the HD615, in particular since there's a remarkable frequency difference between the three variants, with the lowest one running at 900MHz, the mid one running at 950MHz and the top one at 1050MHz.
As I'm considering switching from the m3 to the i5 or i7, this information would prove very valuable to me in deciding which model should I switch to.
I'm interested, in particular, to the results that would come from passmark's software, as they provide comparison between many different card variants and would allow me to better understand where the three models sit compared to my current laptop.
Here's the website I normally use to get this information:
They do list an HD615 model, unfortunately they don't say at which frequency it runs.