ngl Thermalright Extreme Odyssey 12.8W/mK 2.0mm is the best value choice, but Gelid Solutions GP-Extreme 12W/mK 2.0mm is a lot softer and more forgiving if your measurements are slightly off.

Saw this earlier but just getting back to it. Quick question tho, which specific 3080 model do you have? Different AIBs have varying tolerances and it really matters for mounting pressure. If you want to keep costs down, Arctic TP-3 Thermal Pad High Performance 2.0mm is a solid budget pick with great compressibility. Or check out Computer Systems K5 PRO Viscous Thermal Paste if you dont want to waste cash on several different pad thicknesses.

I have been thinking about your 3080 situation for a few hours now and honestly, if you want the absolute best results, you should just go with Fujipoly. You cant go wrong with their high end stuff, even if it is a bit more expensive than the usual brands people usually talk about. I have used Fujipoly Sarcon Thermal Pads on a bunch of 30-series cards and the results are usually way better than the stock junk manufacturers use. One thing to watch out for tho is that the really high performance pads are often quite stiff. If you get something that doesnt compress well, you might end up with a gap between the GPU core and the heatsink, which is a total nightmare for your temps. If you want a brand that is a bit easier to work with but still premium, just get any of the sheets from Kritical. Their pads are specifically designed for these types of high-power cards and they are a bit more squishy. Cost is definitely a factor because the good stuff isnt cheap, but honestly, look at it as an investment. Spending more on Kritical Thermal Pads now means you wont have to worry about your VRAM throttling or the pads drying out and leaking oil all over your PCB in a year. Just take your time with the install and make sure those 2mm strips are cut exactly to size... it makes a huge difference.