Isn’t that processor almost 15 years old? Nor sure what kind of price is alright for that. 250 seems a bit much but I don’t really know. I mean it’d probably work fine and 24GB is plenty of RAM for a few selfhosted services. I don’t think you need a graphics card for most services. Jellyfin can make use of it. Or use the encoder that comes with the iGPU in the processor. And maybe the machine learning features in Immich…

No idea about power consumption. I don’t know where you live, some countries have really cheap electricity. Some don’t and you maybe don’t want to run a random (old) gaming pc, because some waste a lot of power and some don’t and there is no good way to tell except measure it.