What I've found thus far;
Radeon 8970M - 100W power consumption https://www.notebookcheck.net/AMD-Radeon-HD-8970M.90656.0.html
Radeon M290X - from what I gather, it's almost exactly the 8970M but supports DirectX 12.
Radeon M390X - 75W power consumption, along with more compute cores and stream processors. https://www.techpowerup.com/gpudb/2732/radeon-r9-m390x
Well, I got a new GPU to experiment with.
Old - 8970M 2G
New - M290X 4G
Looking at images, there's a ribbon cable connector on one side, but I'm seeing the same M290X 4G with and without it. I guess I'll find out shortly if I get any issues.
I pulled my GPU out, just to check it over, and make sure everything appears good, mounting wise, with the replacement. Upon removal, I noticed with taking off the old thermal grease, the garbage used by the factory, actually separated. I could visibly see a oily substance on the GPU core, while almost every last bit of the grey thermal compound had squeezed out. From here, I added some of my synthetic nano paste, and put it back in for the time being. Got bored, and installed PUBG back on the laptop, oddly enough it worked flawlessly for the most part without error like it had before. Either way, the new GPU will be DirectX 12 compatible and has 2x the GDDR5 memory.
I keep doing more research and I've found the following from Wiki toward the bottom for the Mobile GPU's on each wiki page. It appears I made the best choice in getting the R9 M290X, as it consumes the same power (give or take) as the 8970M. The R9 M390X actually appears to consume just a bit more, and I'm not sure that would be a good idea given it pulls power through the slot. I'll leave it with these upgrades and just enjoy it until it needs replaced entirely!
~Radeon HD 8970M - 100W power consumption - DirectX 11 compatible.
~Radeon R9 M290X - 100W power consumption - DirectX 12 compatible. Same PCB layout as the HD 8970M
~Radeon R9 M390X - 125W power consumption - DirectX 12 compatible. Similar (one oddity off to the side) that may require cooling, that otherwise isn't there on the HD 8970M or R9 M290X.
(Neptune XT) 8 January 2013 1280:80:32 850
72 2304 GDDR5
4 1200 153.6 100
(Neptune XT) 1 May 2014 GCN 1st gen
(28 nm) 1280:80:32:20 850
900 28.8 72 2176
256 4 1200 153.6 100
(Amethyst XT) 2015 GCN 3rd gen
(28 nm) 2048:128:32 Unknown
723 23.1 92.5 2961.4 GDDR5
256 4 1250 160 125