[SOLVED] Testing used GPU in short time

[Sams78601]

I am buying used Asus RX 570. Because of the mining craze I see a lot of used RX 570's dying. What test should I run to see if it is performing correctly. I would have approx 30-45 minutes with buyers PC. Should i run Furmark? Or should i run unigine heaven or valley?
What tests should i run and at what settings?

 

[NightHawkRMX]

Look at gpu-z to make sure it ahows up as an rx570 and all of the specs are as they should be.

Run unigine superposition and furmark for a few minutes. Make sure you notice no artifacts and monitor temperature to be under 80-85c.

Also observe the gpu under load.
Make sure it isn't making any whining or bad fan noises. Also make sure the fans all spin well under load.