iMac with egpu+bootcamp
I have an 2017 iMac (5k, 27’) and I use bootcamp and osx too. I wondering an egpu (razer core x) with a vega 64. I don’t want to use any other displays or anything, only the mac with the egpu. My question is it possible to do or not? As I know, from 2017 the iMacs supports the egpus on osx but I don’t know anything about the bootcamp part. I love playing with windows games so the vega 64 would be a good upgrade for my gaming experience, also it would be great to support my vga on osx too.
I would run some benchmarks in Windows with your current setup using something like Heaven. Then compare the results to the Heaven benchmarks in this forum with a similar eGPU you are looking in to. Problem is most people are using external displays, so you can't use them as a direct comparison to your situation.
Your are going to deal with some severe performance loss using the internal display, even with a TB3 connection. I believe CPU-intensive games really take a beating when using an eGPU.
Not saying it can't be an enjoyable experience. I occasionally use a 2015 iMac 4k with a 1070 eGPU, using the internal display. However, my iMac only has a weak iGPU. Also, due to the fact that I have a TB2 connection, I'm limited to 1080p/1152p for 60fps. It still looks pretty good considering I'm using a 21.5" display. On a 27" display, you are going to want to target 1440p for gaming. Not going to lie, it is going to be a bad value proposition for you. At most, you are going to get maybe a 20-30% improvement when you consider the internal display penalty.
What if I buy a new monitor next to the iMac? Can I buy a gaming monitor with 144Hz or I need to compremise with something because of the mac? Like Can I choose any monitor or it has to be something special input or something?
@zucca Any display should work but some features might not be usable. For example, macOS doesn't enable FreeSync or Gsync. Those feature will work in Windows if you can get the eGPU working in Windows.