Have you tried this: http://forum.xda-developers.com/show...php?p=46388128
? To have less thermal throttling, stock is too agressive.
It was almost the same thing with my D802... about 28 000 before, about 36 000 after. In Antutu it's not just about a few FPS difference that the overall score is impacted by almost 8 000 points or even more (compare the detailed score).
In any case, even with the mod above, let your phone cool down before running a bench.
Sent from my LG-D802 using xda premium