Last month, YouTuber Austin Evans got his hands on the new PS5 revision that is about 300g lighter, has a new screw and a smaller heatsink. He also did a rudimentary temperature test which showed that the new model was a few degrees Celsius hotter at the exhaust vents. This led to his conclusion that the newer model is worse than the original where cooling is concerned. Another YouTube channel has since done more detailed testing, and have come to the opposite conclusion.
YouTube channel Hardware Busters International has gotten their hands on the new PS5 revision themselves. Going straight to the temperatures, Hardware Busters also found that the new model is hotter at the exhausts, by about 2.5 degrees Celsius. Memory and VRM temperatures are also higher on the newer model, by seven and 1.3 degrees Celsius, respectively. But most importantly, the APU was a whole 11 degrees Celsius cooler, rather than warmer.
There are other small differences between the two PS5 models. Despite running the same fan at the same speed, the newer revision is about one decibel louder. The APU also consumes very slightly more power, with the biggest reading difference being 4.5W.
Hardware Busters note that while they were lucky to have both the original and new revision PS5 running the same fan, their tests are ultimately comparing one of each. So the numbers may be a little different if someone were to manage to get their hands on more PS5 consoles and run similar tests. But ultimately, the more detailed testing probably does mean a more accurate result, which suggests that the revised console performs its cooling functions better than the original.