TUM_APISAK has uncovered two separate Radeon Navi engineering samples, one of which features the device ID 731F:C1. According to the readout given by 3DMark, the card sports a GPU clock of 1GHz and 8GB of memory clocked at 1.25GHz. If we assume GDDR6 memory, which is expected for Navi products, we're looking at an effective clock rate of 10GHz and total bandwidth of 320GB/sec.
A second card was spotted in an Ashes of the Singularity (AOTS) benchmark, where it carries the device ID 7310:00. In the Aztec Ruins High Tier benchmark, we see a score of 1520 frames which translates into 23.6 fps. On the Manhattan benchmark, it achieves 3404 frames, which translates into 54.9 fps.
If those performance figures in AOTS seem a bit on the disappointing side to you, we have to keeping mind that these are probably prototype devices running unstable drivers at this point. This could be confounded by the fact that we could be looking at low-end Radeon Navi hardware.
Whatever the case, enthusiasts are expecting big things from Radeon Navi hardware, and AMD is going to need a real "winner" to take on NVIDIA's top-to-bottom line of GeForce GTX and GeForce RTX Turing graphics cards. The latest rumors suggest that AMD will launch a Radeon RX 3080 XT during the third quarter, which will be based on Navi 10 with 56 compute units and 8GB of GDDR6. AMD is reportedly targeting the GeForce RTX 2070 with respect to performance at a price tag of just $330.
We should mention that NVIDIA isn't exactly sitting still either. It's been reported that the company is looking to tweak GPU and memory speeds on its GeForce GTX/RTX families to combat any perceived Navi threat from AMD.