Is the Vega 56 a significantly better GPU than the 48?

[Whackintosh]

Like many, I'm going back and forth between buying a maxed out 2019 5k iMac or a refurbed base model iMac pro for $1000 more (which is kind of a fortune, and is way more than I'd like to be spending).

I feel like the 48 would be more than enough for me in terms of video editing and the like, but I've been told that it's too underpowered to be used for VR experiences (looking more to watch narrative shorts and docs, not gaming).

Would the Vega 56 work well for VR while the 48 wouldn't, or are neither especially well suited for it?

 

[Bohemien]

I think it's comparing apples to oranges, as the 56 comes in a completely different hardware environment than the 48... if they both were available in the iMac Pro, it'd be a fairer comparison. The number designates the number of compute units - 56 vs 48 is only 17% more, so from GPU power alone, I wouldn't expect the Vega 56 being a significant upgrade over the 48. If you look at the Geekbench scores, you see an average of ca. 158K for the 56 vs. 137K for the 48, which is 15% more, so this seems to scale with the number of compute units. So I'd say neither the Vega 48 nor 56 would be too well suited for serious VR applications, at least that was what I read in the various discussions that touched the subject (without being into VR myself, so I haven't tried it).

If you take the different architecture of the machine into account though (different CPU, cooling system, internal SSD RAID), I think the iMac Pro can have a significant benefit over the top-spec iMac, for those who are willing (and able) to pay the price. (But it might be due to a refresh soon, as the iMac's i9 comes pretty close to what the 8-core iMac Pro can do, when you look at CPU benchmarks only.)

 

[mikehalloran]

Significant depends on what you're doing. Large graphics files or AV rendering, yes. Some say that certain games benefit—not being a gamer, I can't answer to that.

As to a possible refresh, those aren't likely to be in the Refurb store for a long time. I certainly wouldn't wait on that.

 

[codernova]

Newegg recommends a 970, 980, or R9 290 for VR. The Vega 48 performs slightly better than each of those. So I'd use that to mean that the Vega 48 will work for your VR adventures.