Now Ryzen 7900X is cheaper than 7900 what is weird. Is it possible to run 7900X undervolted to reach the low power consumption of Ryzen 7900? If yes, is it better to buy this cheaper 7900X or 7900 which has 65W TDP?
Yes get the x variant, its easy to limit, if you dont need the extra cores get the 7800x3d
You won’t be changing the voltage on the CPU, but there’s built in settings to limit the TDP down to whatever you want. If efficiency is also your goal you also want to limit the maximum clock speed (also in the same software).
do i need the mainboard with the “highest” chipset or the with the cheaper chipset it will be possible too?
In theory the A series chipset will run a 7950x3d or whatever the highest end CPU is. It’s the power delivery of the board that matters more. Since you plan on underclocking it then in literally any board should work just fine with it.
I wouldn’t cheap out that much on a board. Get a reasonable B series board, not some A series or bottom of the barrel B series if you’re pairing it with such a high end CPU.
Why any of those instead of the 7800x3d?
You cna use eco mode in UEFI BIOS to limit the power draw. It’s easier and morenreliable than the software (ryzen master) method.
Thank you all for your help.