I predict an overclocked 8120 will outperform a stock 1300X for your workload. The FX series is better at handling multi-threaded tasks rather than multi-tasking, so despite the 1300X (even overclocked) having better IPC, I think the 8120 would be slightly better for video editing, albeit, a lot more power-hungry. In terms of gaming, I think the 8120 will likely be better for newer titles but the 1300X is better for "last-gen" titles. But again, power consumption, and it wouldn't be a big difference. Overall, I wouldn't consider the Ryzen 3 series an upgrade, but rather side-stepping. With an FX 8370, a Ryzen 3 might even be a downgrade. If you had a FX 6000 series CPU, then I'd say a Ryzen 3 would be an upgrade. Personally, I'd say cancel the order for the 8370, get yourself a better heatsink (maybe one that will be compatible with a socket like AM4 for future-proofing) and push your 8120 a little harder.