I use the new EK Velocity block on the Ryzen 7950X and it was the easiest install.
I do as well.
This specific block. I lapped the base though. It really wasn't all that flat to start with. I could visually see the ripples/waves in any reflection. Doing that improved thermal performance significantly.
I did notice that mechanically, the CPU chiplets on an AMD7950x are located lengthwise along the lower edge of the IHS, when holding it upright with the AMD logo at the top. This waterblock runs the channels side to side, with the jetting slot in the middle from top to bottom. This is actually ideal for the 7950x. Additionally the internal jet plate allows for more water flow over the chiplets, and less over the area where nothing is under the IHS. So really it is set up really well in a mechanical sense to better cool dual chiplet CPUs.
Also, laying the block flat on its top before mounting, and spraying some silicone lubricant into the gaps where the mounting bolts come out of the bottom and letting it sit for a while really helped with making the mounting easier. The bolts/springs were very "grabby" without doing this and made the bolts prone to snapping off the fragile tip where the Torx bolt fits in. That happened to one of my bolts all too easily, but fortunately EKWB did ship a spare mounting bolt, so clearly they're aware that this is an issue.
Keeping in line with the mechanical layout of the 7950x, I found that the best way to apply the thermal paste was like drawing an H on its side. Basically a line of thermal paste over the chiplets. A line straight up the middle to catch the IO die, and a thin line across the top for coverage. I found that this worked better for me that the "pea in the middle" method, purely because of how the chiplets are arranged on a 7950x.
After all that, I've never seen my CPU hit above 90C in HWInfo95 even when pulling down a 265W all-core load whereas when I first mounted the block before doing all of the above it would still thermally throttle at 95C.
So for a 7950x I do believe it's one of the best blocks out there, but it does require a little extra care and attention to get the most out of it.
Edit: Oh, the block I had on before was
this one but it was unable to stop the 7950x from thermal throttling. I largely put that down to the channel/jetting being the wrong orientation for the 7950x.
