RE: Inspiron Desktop Gamer PC
That system will handle just about anything you throw at it - I'm typing this on an R5 6-core with an RX580 and it'll handle anything -- with the two extra cores, it'd be even better. The downside of all pre-built "brand name" systems is that they're not very upgradeable -- you will face proprietary power supply connectors, case limitations, etc. down the road -- but if you're not worried about that, the Dell system will do just fine.
If you are, a home-build (or a build by one of the smaller boutique builders that use standard parts) might be a better idea. You will likely have to stretch the budget a couple of hundred dollars, but you can then choose your power supply (mine is 750W) and be set for future upgrades.