Guess GPUZ doesn't show you, although pretty sure it used to.
Either way, using the TFLOP formula, if they are indeed using a 480 downclocked, I found it's MHZ speed.
Formula is: Texture Units * Raster Operators * (core clock) = GFLOPS
So plugging it in would mean, 144*32* (in this case) X
I found the range would be from 910mhz to 912mhz. Which covers 4.193Tflops-4.202Tflops. As close as it'll get. To put into perspective though, This would be a 354mhz downclock on a standard 480. Quite a bit of processing power there tbh. With a PS4 Pro TDP already near 300watts, they probably could have hit a 1ghz wall and be good on power. just another bragging right for console kids.