Radeon RX Vega64 is noisy when gaming with the default voltage/power settings. How hot it is depends on how much cooling you're applying. My reference model runs between 65°C and 70° with the fan at 50% to 55% output. I intend to hold on to it at least until Navi 12 (Rumored to have 64 CU vs. the 40 CU of the Navi 10 in the Radeon RX 5700XT) arrives. If I am more patient, I will wait until AMD's Navi 23 or NVidia's 7nm Ampere GPUs (GeForce RTX 30xx) arrive next year before I upgrade. Intel's Xe purportedly will arrive next year, too.
1: i7-9700K, NH-D15, Z390M Pro4, 32GiB, RX Vega64, ½TB 960Pro +2TB MX500, Define Mini-C, SSR-850PX, LG 32UD99 + UltraSharp U2410, RK9000V2-BR
2: R5-3600X, Wraith Spire, B450M Steel Legend, 32GiB, RX5500XT, 2TB SX8200Pro, P160, SS-660XP2, TV, G610