Ones that are built into the CPU's hardware but you have to pay extra to unlock like a DLC for your CPU. That's not a joke, Intel's new Xeons are like that.
Yeah its crazy. And according to Wendell at Level1Techs its actually a huge benefit but yeah, especially at a datacenter scale I can't see anyone buying chips with dlc. Especially with Epyc currently spanking everyone's butt right now.
Honestly, it's probably more worthwhile to rent a GPU on the cloud rather than buying one for this purpose. Unless you are either working with AI or doing something serious with it, it's likely the better (and more cost effective) option either way. Hardware for training is fairly cheap.
On 1st gen ryzen cpu (until rzen3), don't have branch recording with "perf record -b"
So no way to make your program +15% faster with profile data/PGO/FDO without effort. 😞
I bought an expensive custom built PC with a threadripper CPU on it and they changed socket type for the next generation. And then they didn't release any, anymore. Just sucks to invest.