Can anyone tell me what PC will draw more power?
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.
Why not check online for each component for its max watt?
AMD FX8350 is 125W max Xeon E5645 is 80W max
Then the only difference is the motherboard, right?
And also, the Xeon has integrated graphics but the amd does not. If you will let the amd do a lot of things with video, it needs a video card or else the cpu will need to do all of that. On the other hand, if the machine main task is to for example render videos, an integrated GPU in the Cpu will not get you far either...
It depends on the application/duty, but maximum/rated power is not usually relevant for power consumption on home servers like this - they're rarely running at mother than a few percent load.
Idle power consumption is the main concern. Server boards often have a lot of NICs and chipsets that don't idle well. Consumer gear is generally much better for that.
Neither Westmere nor the AM3 platform are known for low power consumption. A modern LGA1150 or later desktop platform would probably be preferable.
You are absolutely right. Assuming the home server is probably not serving thousands requests every minute or mining bitcoin but just a file server or something that is idle most of the time.
Max wattage would be under load. OP has said the PSUs are rated for 750 vs 600 (potentially 750x2 if they plug the rack’s second psu in).
That’s your max usage right there. But that’s assuming everything tops out and it’s not a valid assumption.
In any case I suspect the pc will be more effecient on account of the server basically being overkill. Substantial overkill.
I do not agree with that.
A PSU is the maximum what all the components combined are allowed to use. No more power than that is possible. If a system needs more than it's PSU can deliver, it will become unstable (data loss, random restarts, etc.)
The 2x750 is a redundant setup that servers have. Servers need to be able to run 24/7. With redundant PSU if one PSU has a failure, the other PSU will take over. Without any restarts. You can just pull the plug out of one of the PSU and all is just fine.
I do agree with you that the max wattage is under load. Most home servers are running idle most of the time anyway.
that's why there's 2x 750's instead of a single 1500 watt, yes. but they're frequently capable of drawing more than the 750 watts under high demand loads. which is kinda why I put that bit in parenthesis. The OP has said they have it unplugged.
first point is literally what I said.