GT 1030 has a 64bit GDDR5 at 6008MHz memory with 48,06GB/s memory bandwidth
RavenRidge with 128bit DDR-4 3200MHz memory will have 51,2GB/s memory bandwidth
A desktop RavenRidge 65W TDP top SKU should be close to GT 1030 performance, much like Kaveri was close to GT730 GDDR5 64bit.
1st issue: RR is spec'd for DDR-4 2400MHz max, you are essentially invoking running overclocked memory.
2nd issue: It's shared bandwidth for the APU, and dedicated for the dGPU.
3rd issue: NVidia appears to be more efficient and using memory bandwidth than AMD.
I bet GT 1030 kicks RR ass in gaming.
But hey it might beat a Radeon 430/530 rebrands running old 28nm, GCN 1, on 64 bit bus, if you are so keen on having it better a standalone card.
But no one is going to build a new dGPU inferior to an APU, that would be utterly pointless. You can really only expect it to challenge old GPUs.