“Freezes” how exactly? What are the exact symptoms? “Freezes” how long into the training?
Based on the system specifications, the PSU wattage seems to be sufficient. What is the vendor and model of the PSU? Check the GPU auxiliary power cables: there should be two 8-poin power connectors, and the cables connecting them to the PSU should not use converters, Y-splitters, or daisy-chaining.
Use nvidia-smi to monitor GPU power and cooling. Remove overclocking of any overclocked components if possible. For example, the DRAM and GPU appear to be vendor-overclocked parts. Running the memory at DDR4-2666 speeds with CL=19 looks like worth a try.
The system components suggest a self-assembled “tweaked” gaming rig trying to get the highest performance from low-budget parts. Not always the best basis for a rock-solid compute platform.