To what degree? The Uni-power's boost goes from x50 to x7500. However, Thor at his a-game was a planet buster and yanked the midgard serpent clean off the earth even though it weighed as much as the planet and was coiled tightly around it. This puts him well over six sextillion tons in strength. Grey Hulk is normally an 80 tonner so that puts his starting strength anywhere from 4000 tons to about 600000 tons, which means Thor is going to have a starting strength that's at the very minimum, a hundred quadrillion times higher. To put this in perspective, that is about as many seconds as the universe has been around. So going by calcs, Thor one shots Hulk.
I dont see what calculation people are running. Thor and Prof Hulk fought in Hell with Thor gaining the majority without really totally dominating the fight. The fight look even, with Thor being the likely winner. Thor did not have his hammer, Hulk had to restrain his anger.
Once you boost Hulk's strength a 50 times, there is no way in hell Thor is stronger unless you extremely biased.
And Midguard serpent was never said to weight as much as a planet, and what Thor bust was likely a planetoid as oppose to a planet and was questionably at warrior madness (not to mention the hammer enchantment boost the striking power). Also you have the whole Thor with Odin Force needing BRB to lift the Asgard. Not to mention its not like Grey Hulk himself doesnt have much higher feat, i.e. breaking an asteriod twice the size of the earth (and he was propelled by a spring).
So yeah lets not downplay hulk and ridiculously overplay Thor. Thor is going to be the under-dog as far as strength and durability is concerned against the uni-power hulk, for anyone looking at it objectively. Thor has versatility, and outside of Godblast or a very amped up winds of 1000 worlds, i dont see anything on Thor's armory to really take down Hulk with so much boost, and even those are questionable.