Dell R720 single CPU with single PS

[palali]

Hi. My first post here - so go easy on me

I recently bought a Dell R720 server with dual E5-2620 CPUs. This is going to be a home file server and a media server. After some tests, I realized that I don't really need 24 CPU threads for what I'm doing. So, I'm thinking of removing one of the CPUs. My questions are:

1. Does it matter what CPU I remove? Or does CPU1 needs to be in place for single CPU use case?
2. Do I need to put something like a blank "terminator" in the empty socket?
3. Can I also remove one of the two power supplies if I use only one CPU? The power supplies are 750 watt version.

I understand that certain pcie slots and memory slots won't work with single CPU and that is okay. My main reason for wanting to remove a CPU and PS is to lower the energy consumption.

Thanks in advance.

 

[j_h_o]

1. You need to remove CPU2, and leave CPU1.
2. You should cover the socket, but it's mostly to prevent damage to the pins and to keep things clean. It will work if just left uncovered.
3. Removing another PSU may not save a lot of power, and it will likely significantly increase noise. How important is that to you?
4. But you may need to move RAM around, depending on which slots are in use. Removing RAM will likely save a lot of power, too. How many sticks of RAM are installed?

 

[palali]

Thanks for your reply.

#1 and #2 make sense. What do you suggest to cover the empty slot?

#3: I would like to save power as much as possible since I'll be running this server 24 hours at home. It's not the cost that I'm concerned about - it's more from the perspective of environmental impact, even if it saves a few watts. I have a Kill-a-watt - so, I can measure power usages with one or both CPUs to see if that makes a difference. I just wanted to know if one power supply was sufficient to handle a single CPU load. Noise is not really a concern because the server is in the basement

#4: great suggestion about the RAM. The machine has 32GB with 4 sticks and they are 1.5V modules. I could go down to 16GB without impacting performance. Thanks for this idea.

 

[tritron]

I would check power profile to os controlled If you are set to to performance it uses whey more power. I would leave ram you only save 5 to 10 watts. You eant to make sure bios idrac is up to date I updated my r630 to latest firmware and saw it go down with 50 watts with 64gb ram xeon 8 core.

 

[111alan]

The PSU should usually be enough if you don't have a lot of storage device or something like graphic cards attached. E5-2620 only uses 95w, that is at most 110w or less than 10A into the CPU VRM. Also the dual PSU in servers are usually aiming for redundancy rather than providing more power. You can check the sticker on the PSU to make sure.

And something to notice, your load(relative to PSU's rated output) will determine whether removing a PSU will improve or decrease efficiency. Usually a PSU will have an efficiency curve like below, when the load-percentage is low the PSU itself wastes more power so it's better to use only one, while when the load is high you can use 2 PSUs to share the load and increase the efficiency.

 

[Lost-Benji]

I personally would leave both P's in and as well as both PSU's. Go into the BIOS and tame down the horsepower from "Performance" to Economy mode.
If you do yank out a processor, you are going to loose PCIE slots.

 

[neb50]

Taming a 12th gen Dell PowerEdge

Gotta love decommissioned servers... Anyway these are starting to hit the used market and are getting affordable. The 2U series such as the R720 would make a great medium sized unraid box. They can use V1 and V2 XEON 2XXX series socket 2011 chips. They can handle ALOT of ram, last head count was ...

forums.unraid.net

I started with this guide on how to reduce the power consumption on my r720's. I also use FreeNAS with a fan script to monitor the drive and CPU temps and reduce the fan speed to lower the noise and power draw even more.

 

[tonyjadd]

I have a Dell T610 that I'm pretty happy with, except for the old and slow Nehalem era CPU which burns a ton of power. (IIRC I have L5630 dual sockets.) I'm using a reflashed 9211-8i for IT disc access.

You can get inexpensive AM4 socket motherboards for under $100, and a Ryzen 5 2600 for about $150. Put those together and I'd probably break even just on power use in less than a year. So I'm wondering if I could simply rip out the 192.168.100.1 192.168.1.1 existing motherboard, but leave the backplane, power supply, etc, put in a new AM4, and expect everything to e to be tricky business.