Unusually poor performance on old AMD APU (A10 5750m)

I recently installed Mint on my old original gaming laptop from 2012ish and this OS really brought it back from the dead. I used to game on this laptop for many years until I built my first desktop in 2017, so I’m pretty familiar with its limitations. I’m not delusional; I’m not expecting to run anything high end on this. But I do very distinctly remember getting playable framerates on Borderlands 2 barring some very intensive locations.

So here’s where my issue begins. I thought this would be a perfect system to play some newer indie games on, so I loaded up UFO 50 and Hazelnut Hex and I’m both games I got literally 5fps. I couldn’t get a single frame higher than 5. Something that stood out to me was that Steam’s system monitor overlay had my CPU showing a cap of 1.8GHz, when TechPowerUp’s database shows the 5750m as having a frequency of 2.5GHz with a boost of 3.5GHz. So it looks like I’m not even getting half of what I ought to out of the CPU. Also GPU utilization was showing 0% but I’m not really familiar with how APUs interact with that on the Steam overlay. For all I know that could be how it’s supposed to work.

I loaded up some older indie games from around the time this chip was new (Dust: An Elysian Tail and Titan Souls) and I got a perfect 60fps on both, so as best I can tell the processor is actually functioning properly. I also booted XCOM 2012 an I was getting only about 25fps on the title screen, and that also feels lower than I should be for this system.

So in my little bit of digging I found that 1) newer lightweight games run completely awful even though I believe the hardware should be more than sufficient to handle them 2) the cpu seems to not be achieving its specified speeds 3) older games contemporary with the laptop itself seem to be actually functional but still not up to the level they should (I think).

Also I just repasted the cpu chip with KPx because the original paste had dried out and was running the fan max right from boot. Since I did that it runs quiet again, so I know the cpu is not thermal throttling.

Does anyone have any advice to fix this issue? Is this level of performance to be expected? I saw that it seems the most recent Linux drivers for the 5750m were from I think September 2015, so that could be another reason why games more recent than that run poorly.

Any info or experience would be very appreciated! Thanks to everyone.