MAMEWorld Forums - Hardware - Buying new PC, help me choose processor & GPU

My old PC crashed so I'm finally going to buy a new one. I'll be using it for basic everyday computing as well as playing MAME, which is the only type of gaming I partake in. I only have mediocre knowledge of computers and I don't know how to build them myself.

I'm leaning towards buying the Dell XPS 8930.

http://www.dell.com/en-us/shop/dell-desk...op/dxcwvmax004h

I have a couple questions:

1) Should I upgrade the processor i7-8700 to the i7-8700K? It's a $100 extra. Will more games in MAME run at full speed with the upgrade?

2) Should I upgrade the video card? If so, to which of the 8 video cards they have listed should I choose? Will more games in MAME run at full speed with the upgrade?

(I'm trying to keep cost at a minimum of course. But at the same time I want a good PC that will last for many years.)