I'm really amazed at all the DIY OC's who believe there is ONE best way, one best product for this, and for that. I make whatever I have work best. It's a matter of skill, not magical knowledge!
If I don't have the right thermal paste, I'll just put a 2.0A fan on the heat sink. Gets the temp nice and low. I just want temps low 'enough'. If I want really low temps, I wouldn't use water. I'd use Peltier chips. That will get temps below any water-cooled system!
So, if you know what you're doing, you realize there's always a way using whatever you can get your hands on at the time. Absolute 'bests' are not that. They're the best under a specific and rigid set of conditions that simply won't apply in every case.
When I apply paste, I couldn't care less what the temperature of the compound is. I'm going to run a gpu bench, get that gpu just smoking hot, and twist the heatsink/fan back and forth to distribute the paste nice and thin.
Pretty tough to heat the paste up to 80C before you put it on the gpu. But if you run a gpu bench, it'll get the paste nice and spreadable. I always use 2 lines part way across, not to the edge.
But everyone wants to be the authority,so they conduct these experiments with surprising results. But that's by design, for publicity. Just pick a good way to do things. There is no 'best' way to do DIY PC STUFF.
You just make it work with what you have. As time passes, everyone amasses a lot of xtra parts and supplies, so you get more to choose from in your projects.
I've been in the DIY PC racket for 22 years, and I've got boxes full of parts and supplies, and at least 20 dektop PCs piled up for salvage, and 15-20 laptops. I've got boxes of salvaged PCBs, power supplies, you name it; all kinds of adapter boards.
I pulled a capacitor off one of my salvage PCBs, and soldered it into my TV, because the power board had failed, and it's too much trouble to go out and get another tv.
There's just no substitute for using the mind to solve problems, rather than seeking that elusive knowledge, which once found, ensures success, because it doesn't exist. It's just a variation on gambling and/or investment systems that always pay off! No such thing.
And there is no magical way to apply thermal paste that ensures success every time.