Imac Goes To White Screen And Won't Install

I have an older iMac, which was given to me, I believe it's a 2012. I booted it into recovery mode and erased the HDD using Disk Utility, following which I tried unsuccessfully to reinstall MacOS. Using Command-Option-R it booted to internet recovery, I connected to a network via Ethernet, it went through the initial progress bar with the spinning globe, and once complete it showed the typical Apple startup logo, with a progress bar beneath. The bar got about 2/3 complete, then it just flipped to a white screen. I tried this a few times with the same result. I then attempted to install El Capitan from a bootable USB installer I created, which did the same thing (without the globe obviously). I don't think it's a hardware fault, because I can boot the computer into Windows using a copy I have on an external HDD, and it works fine. It just doesn't want to reinstall MacOS. Any thoughts?

 

you can look here:
https://eshop.macsales.com/blog/40844-how-to-recover-from-a-white-screen-when-booting-a-mac/
they seem to think it is a hardware problem, but they do give several options to try.
i had an imac at one time, but it developed heat problems after a couple of years.
don't know what else to suggest, good luck with it!

 

Yeah I've done literally everything possible from that page (can't boot to safe mode or verbose with a raw drive), no luck. Another thing I just tried was installing High Sierra to an external drive using another 2011 iMac, tested it on the known working machine (worked), but when I tried to use it to boot to the problem computer, same white screen after 2/3 of a progress bar. So it's really starting to feel like a hardware issue, but like I mentioned, it runs perfectly when I boot Windows to it. So weird. I also did the RAM dance, no luck.