[jason ryan] “Windows 7 Ultimate 64 bit “
Resolve officially supports only Windows 10 at this point so you might run into some snags.
[jason ryan] “AMD Radeon R5 200 series graphics card”
You didn’t give any specific specs so I’ll have guesstimate that this card has either 1 or 2 gigs of VRAM. 2 gigs is barely enough for HD footage and this is probably why your computer is crashing.