Sooo, I actually went through this exact same panic when I built my 7950X rig for video editing last year. I kept seeing those 95°C benchmarks and honestly, it freaked me out a bit cuz I didnt want to fry my chip during a 4-hour render. I ended up trying a couple different setups because I'm kinda paranoid about thermals... and my wallet. For your situation, I'd say the ARCTIC Liquid Freezer III 360 is basically the king of value right now. I mean, it's got that extra thick radiator and the little VRM fan which actually helps keep the motherboard components cool under heavy load. In my O11 build, it fit fine, but you gotta be careful with the top clearance. The main pro is the price-to-performance ratio; it's hard to beat. The downside? Its kinda bulky and the installation is a bit of a workout. On the other hand, you have something like the Corsair iCUE LINK H150i RGB Liquid CPU Cooler. It's super sleek and the cable management is amazing, which I love, but you're paying a HUGE premium for those fancy fans and the ecosystem. In my experience, the actual cooling difference on a 7950X is pretty negligible between these two. Both are quiet enough at idle, but the Arctic fans have a slightly lower hum that I prefer for long work sessions. Honestly, I guess my lesson learned was that these chips are actually MEANT to run hot. As long as you aren't throttling, you're fine. I'd stick with the Arctic and save that extra $100 for more RAM or a better SSD. It's the safer, more practical play imo. Anyway, hope that helps!!

Jumping in here since I've spent way too much time obsessing over Zen 4 thermals. If you're looking for that sweet spot between premium brands and budget picks, I've had great results with the DeepCool LT720 360mm Liquid Cooler. In my experience, it handles the high TDP of the 7950X just as well as the iCUE Link models but for way less money. The pump design is really solid and it doesn't feel like a cheap piece of plastic. Another one I'd look at if you're really watching the budget is the Thermalright Frozen Prism 360 Black ARGB. Honestly, the price-to-performance ratio on Thermalright stuff lately is kind of insane. It might not have the fancy LCD screen or the software ecosystem of Corsair, but for long renders, it keeps the chip from hitting that 95C throttle point just fine. Basically, check out the charts over at Gamers Nexus or Hardware Busters if you want the raw data. They do standardized noise-to-thermal testing which is the gold standard for comparing these fairly. Since you're in an O11, definitely stick to a 360mm... trying to cram a 420mm in there is a nightmare and the tiny performance gain isn't worth the headache imo.

Honestly, even tho AMD says 95C is safe, seeing those temps during a 10-hour render still makes me super nervous. I am all about over-engineering my cooling just for peace of mind and long-term reliability. Since you are in the O11 Dynamic, just a heads up that a 420mm rad likely wont fit without some serious modding... the standard O11D is really built for 360mm setups. If you want something thats rock solid and handles sustained heat well, the EK-Nucleus AIO CR360 Lux D-RGB is probably your best bet. It has a much more robust pump design than the standard Asetek units and the thermal transfer is top-tier for heavy workloads. Another great choice if you care about monitoring is the Corsair iCUE LINK H150i RGB Liquid CPU Cooler. Being able to track your actual coolant temps in real-time is a lifesaver when you are pushing a 7950X for hours. It helps you catch any potential issues before they actually throttle your render, which is basically what you want for a workstation.