Terragen is a really good hardware stress test software
I have a damaged computer at home for the moment (the old computer had a strong overheat damage lately, I have lost few memory and pci slots).
While I can still use some CPU demanding softwares (Clarisse, Modo), Terragen is the only one that clearly remind me there is something with my rig
(system freeze, blue screen, instant reboot, etc).
Not a Terragen fault, as the same scenes render fine at my office ...
Btw yes, 32 gigs is probably the bare minimum these days ...