This is probably a stupid question, since 2 > 1, but here goes…
I have a home server. It’s a ComputerLINK 1U rack server I bought off eBay some years back. It has 2 CPUs, Intel Xeon E5645 2.4Ghz(https://ark.intel.com/content/www/us/en/ark/products/48768/intel-xeon-processor-e5645-12m-cache-2-40-ghz-5-86-gt-s-intel-qpi.html). It also has two 750W power supplies, but I have one unplugged. It also has RAM and 5 HDDs.
I also have the guts of my old desktop PC. The CPU is an AMD FX8350 4Ghz(https://www.amd.com/en/products/cpu/fx-8350). The motherboard is some ASUS model, I forget and don’t want to check right now. A potential PSU would be 500-600W range.
My question: I am considering moving to use my old PC parts as a new home server. One benefit is to cut down on the noise (rack mount PC fans are LOUD). But the real gain I would want is on power savings. So, if RAM and the multiple HDDs all stay the same, but I moved them to the AMD/ASUS CPU/motherboard, can anyone definitively say this will be more power-efficient?
I am not very knowledgeable when it comes to electrics or power consumption, and am just looking for someone to confirm for me. I am aware that the AMD CPU still isn’t an excellent choice for an always-on machine, but it could be an improvement.
Question: does your home server Need to be powerful for what it does? Would a mini desktop PC or a single board computer be able to do the same job as your current setup? Of your main concern is truly power savings, consider those options. Most mini pcs maybe draw 60 watts, most laptops only draw around 15-20 watts, most SBCs only draw around 5 watts max.
The best way to increase energy savings on your currently owned server would be to upgrade your PSU and not motherboard. Get a gold rated PSU certified by energy star as it has at least 85% efficiency. Invest in a kill-a-watt measurement device that plugs into the outlet so you an see exactly how much wattage you are pulling and how much you manage to cut down.