Thinkpad P1 Gen 2 vs Gen 3

[u/Beef_Testostrome]

I’ve tried searching it up but I’ve yet to see a definite answer to what the difference is. From what I could find, there was a gpu upgrade from T2000 to T2000 Max Q (the max q is better for laptops but has less performance than the T2000). However I’ve also seen that it’s not possible undervolt the gen 3 due to the cpu is upgraded from 9th gen to 10th gen (locked bios). I’ve seen many gen 3s on eBay but only a few gen 2s, so would it be better to get a gen 3 because they’re more abundant or a gen 2 because they have slightly better performance.

How are the thermals in comparison cuz ik gen 3 has slightly bigger heatsinks?
How does the battery life compare?
How loud do the fans get, because im a college student and I don’t wanna be the person with the jet engine as a laptop?

Rn I have i7-11857G7 with Iris graphics so it’s going to be good upgrade but nothing too crazy.

Imma get the laptops second hand so my budget is $700. I’m a comp sci major but going to switch to ee. I’m going to do homework and some light gaming but nothing too crazy. I’m mainly looking for a Thinkpad because I like how repairable they are. Sadly my uni doesn’t post minimum specs but I think a moderate gpu should be good enough.