It’s not a simple comparison as it was in the past - let me elaborate a little bit.
Modern CPUs with the Turbo Boost have (as far as I understand it - bear in mind I’m doing this from memory) multiple boost ‘levels’. A CPU will try to always be at the highest level if the surrounding parameters of time, power and temperature are ok.
The Surface at least 2 levels (I think it might be 3 and I will write it down as 3):
Level 2: ~20W TDP, Lasts ~2 Minutes
Level 1: ~15W TDP, Lasts ~10 Minutes
Level 0: ~7W TDP, Lasts indefinitely.
The V’s CPU also has a similar setting - the default setting of the Core Y CPU actually goes roughly like this:
Level 1: ~15W TDP, Lasts 30 Seconds
Level 0: 7W TDP, Lasts indefinitely
Cinebench actually is a bad benchmark in my opinion to compare that as Cinebench is a rather short benchmark - there are better ones for sustained tests as it runs longer and it comes closer to real-world performance.