New Hardware and Windows 7?

Hello everyone ,
Last week I built my new pc with ryzen 1200 Asrock 350 pro4 motherboard, with 8 gigs of crucial ram stick ,power supply 600 watts,zotac gtx 1060 mini 3gb and a 1tb hard drive. Just because I was limited on budget I didn't bought a new case for my system.
Now here is the problem, as I assembled all the components in my new pc and I was in the Bios.All the parts were working fine the processor,ram,GPU and hard drive.But When I started to install windows 7 on it,as I got into the setup both my keyboard and mouse they stopped working and this problem I was trying to trouble shoot the whole night!Now some of you might think that how can u get in the BIOS without a working keyboard?Let me tell you both devices keyboard and mouse worked fine in the BIOS but were not working in windows 7 setup and that was the problem.
Googled the problem ,read many blogs, saw few solutions but none of them were working.
But then I tried installing windows 10 on it and the problem of dead mouse and keyboard was actually solved.
So what I learned from all this is with new hardware go for latest OS and it will save you a lot of time.
Thank you all for reading till end.