Questions tagged [power-supply-unit]

Questions related to power supply units, aka PSUs

Filter by
Sorted by
Tagged with
55 votes
6 answers
13k views

Why do we still use power supplies on datacenter servers?

Computers mainly need three voltages to work : +12V, +5V and +3,3V, all of them are DC. Why can't we just have a few (for redundancy) big power supply providing these three voltages to the entire ...
user avatar
42 votes
6 answers
122k views

Does a 500 watt power supply always use 500 watts of electricity? [closed]

Does a 500 watt power supply always pull 500 watts? Or does it depend on the load being placed on the computer? It's a n00b hardware question. I'm trying to figure out how much it costs to run my ...
Jim's user avatar
  • 1,555
41 votes
3 answers
43k views

How do servers with redundant power supplies balance consumption?

I have several servers from the HP DL360 line (generations 5-8). Each of these servers has two power supplies installed. The 2 power supplies in each server are fed from different circuits. My ...
Travis Beale's user avatar
18 votes
3 answers
12k views

How does a 3-Phase UPS distribute power?

We've got 2 UPSes in our server room. One's 3 phase, and has a 3phase supply, yet the APC network stats thing only says Incoming Voltage: 230.1 Volts The other is a single phase one with no ...
Tom O'Connor's user avatar
  • 27.6k
17 votes
4 answers
3k views

Can Running a Server's Redundant PSU on Different Circuits Damage It?

So I've been tasked to document and review the status of the UPSes for my current employer and identify any changes that need to be made. Generally easy stuff, however I came across a few units that ...
Insomnia's user avatar
  • 507
13 votes
5 answers
45k views

How can I determine the power demand of an HP server's power supply under load?

I bought an HP DL360 G7 1 U rackmount server. I am looking to put it in a colocation facility. The issue is almost every facility I have seen either limits the amount of power I can access or charge ...
AtomicPorkchop's user avatar
10 votes
3 answers
1k views

Can I hot-swap a 2-PSU server from 120 to 240 volts?

I'm migrating a server with 2 PSUs from 120 volts to 240 volts, and I'd rather not take it offline. It seems like I should be able to just move the PSUs to the new voltage one at a time, since they ...
user avatar
10 votes
2 answers
10k views

How can I calculate if a UPS is sufficient for my requirements?

I am not that of an electricity knowledgable person, so I'll try to put as much info as possible. I have a Rack Mount UPS of 1800 Watts Model: PRP 3050 RM (in total I have 2 of these - talking about ...
Saariko's user avatar
  • 1,801
9 votes
4 answers
5k views

Maxing out both PDUs in a rack with redundant power

If I have a rack full of servers using redundant power supplies, and I'm keeping the amps at 80% (16A of 20A), isn't this still asking for trouble in the event of a power loss on one of the circuits? ...
Matt Beckman's user avatar
  • 1,512
9 votes
4 answers
645 views

Redundant Power Supply Sloshing (If sloshing is the right word)

I have a Supermicro Redundant Power Supply with two units in it. I also have two UPS units, one for each of the Power Supplys. I was watching the LCD on the UPSs for the watt usage. The total watts ...
xriri's user avatar
  • 91
8 votes
3 answers
6k views

Power Cables Required to Switch from 120v to 240v for Dell Poweredge Servers

We have a cabinet of servers and other hardware (switches, firewalls, etc) that all are currently running on 120v. I've confirmed that the power supply for all of our devices support both 120v and ...
Dan's user avatar
  • 707
7 votes
8 answers
4k views

Is there a solution against short power outages except UPS?

I encounter very short power outages quite often. Typically they last for just couple of seconds - perhaps the power grid maintenance staff just flips the switch to "Off" and then immediately to "On". ...
sharptooth's user avatar
  • 2,739
7 votes
1 answer
567 views

Is it safe to remove power from a linux computer in run level 0? [closed]

I am working on power supply to a Raspberry Pi where changing the state of one of the GPIO lines shuts off power immediately. Is it safe to do this in run level zero, or is there more shutting down to ...
Xian's user avatar
  • 197
7 votes
6 answers
3k views

Server power supply failures?

I have 6 servers both with 2 power supplies attached to an UPS. I want to add 4 more servers but the UPS is full and due to budget restriction I couldn't buy a new one for months. The 6 + 4 new ...
Kami's user avatar
  • 1,444
6 votes
10 answers
5k views

Do I need some kind of power conditioner or UPS?

In one of my boxen, both my power supply and network card died while in overnight hibernation - why? And: What must I do to appease the electricity Gods so that I don't lose more hardware? In ...
Josh's user avatar
  • 181
6 votes
4 answers
10k views

How do I monitor redundant power supplies on a Dell server?

I'm purchasing a Dell R610 with redundant power supplies. What is the best way to be alerted in the event that one of the power supplies fails? I'll be running Windows Server 2008 R2. Since this ...
user avatar
6 votes
1 answer
2k views

Plug single PSU into two different power sources

We have a rather uncommon situation: We have a server in a computer center. Its got not enough spare space to put in a redundant PSU. Nevertheless, we want to attach the single PSU to both existing ...
roesslerj's user avatar
  • 297
6 votes
2 answers
713 views

Double UPS on high load during power down

To sketch the situation : a bunch of servers (~15 going from 4u to 1u, some redudant PSU some single) 2 UPS (1 APC I can read using apcupsd) 2 PDU So I came upon this situation, and I honestly have ...
SvennD's user avatar
  • 749
6 votes
4 answers
19k views

How to measure server power consumption?

We have data center running more than 2000 servers. We are planning to shutdown the servers on a weekend for cost cutting purpose. How can we calculate which servers are consuming more power in the ...
sanjay p's user avatar
6 votes
2 answers
931 views

At my wits end. What could cause my server to randomly hard reset? (Seems to be related to ZFS)

I have a server that I built years ago that has worked like a champ. But within the past few months it has started to become seriously unstable with no discernible pattern. I have been debugging it ...
Zhro's user avatar
  • 349
5 votes
2 answers
3k views

DL385 G2 powering off after some time

I have one DL385 G2 server that since Thursday is not able to power on properly. I can't figure out what's the problem, since there is no indication neither in iLO 2 log, IML, nor any red/amber LED on ...
Peter Dian's user avatar
5 votes
4 answers
35k views

HP Proliant DL380 G7 won't power on, UID light works, ethernet lights blinking, power button solid orange

Momentary press and long press of power button does nothing. Can get in through iLO but pressing the button there does nothing. This started after our block had a power failure but all our servers ...
Tom's user avatar
  • 419
5 votes
3 answers
6k views

R610 redundant power supply

We are installing Dell Poweredge R610 servers with redundant powersupply's: High Output Power Supply Redundant, 717W So each server has two power supplies. I'm trying to figure out whether ...
wdp's user avatar
  • 53
5 votes
4 answers
56k views

What is the button on power supply of the Dell Optiplex 760 workstation for?

What is the button on power supply of the Dell Optiplex 760 workstation for? There is a small button near LED power indicatior - seems to do nothing when pressed.
tomash's user avatar
  • 216
5 votes
1 answer
6k views

Is it possible to convert 4-pin floppy to SATA power?

I just bought a server and realized that it had power for all my drive bays, but not for the internal SSD I bought for it. It does, however, have 2 free 4-pin floppy power connectors: Is it possible ...
Hubro's user avatar
  • 1,148
5 votes
1 answer
225 views

How to verify power provided to processors is clean

Once in a blue moon, I am seeing a blue screen of death on a shiny new Dell R7610 with a single 1100 Watt Dell-provided power supply on a beefy UPS. BCode is 101 (A clock interrupt was not received......
GregC's user avatar
  • 889
5 votes
2 answers
919 views

Will a 300W psu drain more power than a 100W if the system only uses ~80W?

I have a NFS server that is a old mini-itx motherboard with two 2.5" drives and a no optical drive. Atm. this is powered by a external 100W psu, but I estimate it only need/uses between 60-80W. This ...
eple's user avatar
  • 73
5 votes
1 answer
4k views

spontaneous reboot, machine check events, AMD ryzen [closed]

I've been running a brand new system on arch linux for about 3 weeks, and last night it spontaneously rebooted. There's no shutdown/halt in journalctl at the time of the reboot, so I'm pretty sure ...
Todd Freed's user avatar
4 votes
3 answers
3k views

How many power circuits do I have in a rack?

I'm planning to get some colocation space from someone in my area, and like most companies that offer colocation, ask about power supplies (of course) in the quote form. I'll need a power of 1000W ...
XCore's user avatar
  • 177
4 votes
4 answers
3k views

HP ProCurve 5412zl warm-boots on power failure while attached to UPS

My client's HP ProCurve 5412zl chassis switch reboots on occasion, despite being powered through four redundant power supplies and being under UPS protection. These reboots usually happen during a ...
ewwhite's user avatar
  • 198k
4 votes
2 answers
2k views

Redundant UPS with 2 power sources

I've 2 power sources in my house: One from the national power grid and another from an internal power source. I've several power sockets in my server room from these 2 sources. Did some research and ...
Mário's user avatar
  • 101
4 votes
2 answers
262 views

Does the additional load on UPS in case of grid failure amount to 100%?

The scenario is as follows: Servers are equipped with two PSU's each. One of these is connected to the UPS, the other one directly to the power grid (bypassing the UPS). I would assume that since the ...
Roman's user avatar
  • 3,927
4 votes
1 answer
6k views

HP Proliant DL380 G7 power calculation

HP Proliant DL380 G7 in year of production has alternative PSU: 750W in "performance" configurations with 2 CPU 460W in "base" and "entry" with 1 CPU "Power advisor" calculator is not accesible in ...
Jacek Cz's user avatar
  • 141
4 votes
3 answers
2k views

ipmitool sensor: does not detect backup power supply

Why doesn't ipmitool detect my second power supply? I have 2 powersupplies plugged into my machine, but calling ipmitool sensor only shows PS1: :~$ sudo ipmitool sensor |grep PS PS1 Status | ...
kevlarjacket's user avatar
3 votes
3 answers
3k views

How much power draws a redundant PSU?

One supermicro enclosure comes with "3 SP382-TS 380W Power Modules for a total of 760W". 2x380W = 760W, okay, but there are 3! So where is the missing third 380W equalling to 1140W?? Is it hot-...
isync's user avatar
  • 701
3 votes
1 answer
4k views

5-pin 4-cable connector on SuperMicro server PSU?

I have a 4U SuperMicro SC847 Chassi that comes with redundant 1400W power supplies. All of the internal power cables (ATX, ATX12V, HDD and such) are connected to two circuitboards where the back of ...
tlund's user avatar
  • 241
3 votes
2 answers
1k views

HP Proliant ML310 G4 power supply warning

One of the two power supplies in my HP Proliant ML310 G4 server has an amber/orange LED lit in one of the power supplies on the front panel. Also, the wave symbol is flashing in orange/amber. When ...
Björn's user avatar
  • 235
3 votes
8 answers
632 views

Anti surge protection

Great site - my first posting! I support a number of small business for all things computing. I protect the servers with APC Smart-UPS 1000. The do just what they were bought to do. However, I dont ...
Grimbo's user avatar
  • 31
3 votes
5 answers
4k views

A plan to mitigate PDU failures?

A client just experienced a complete failure of an APC AP7911A switched/metered rack power distribution unit (PDU). This obviously took all of the connected equipment down with it. The equipment is ...
ewwhite's user avatar
  • 198k
3 votes
1 answer
835 views

Understanding ipmitool output for "Power Supply" (PSU)

This Ubuntu server has two PSUs, I just ran ipmitool and it reported as follows: # ipmitool sdr type "Power Supply" PMBPower1 | DFh | ok | 10.0 | 624 Watts PMBPower2 | E4h | ...
guesty's user avatar
  • 65
3 votes
2 answers
4k views

A/B Power Configuration for Server Cabinet

I'm upgrading our cabinet at our colocation for A/B power and wanted input on which of our options are good or bad. First, a bit of an overview of our setup: We currently have a single circuit feed ...
Dan's user avatar
  • 707
3 votes
2 answers
447 views

Power reading 2 amps with 13 servers?

We have a rack in a data center and we became suspicious of running out of power. But our power bar says 2 amps! It has a live indicator, so it's not just one reading. Do you think there's something ...
Jay's user avatar
  • 89
3 votes
1 answer
3k views

Software to measure power draw of HP Server

I'm after some software to measure the power draw of a HP Server, namely a DL360 series. I know Nagios is used for logging and monitering but I'm not sure if it logs power usage as well. I've also ...
tombull89's user avatar
  • 2,964
3 votes
3 answers
720 views

Chasis reset button vs remote power recycle

Ocassionally one of my remote windows servers locks up and must be restarted by pressing the restart button on the front of the case. Since I work remotely I call a coworker to press the button. I ...
steampowered's user avatar
3 votes
2 answers
4k views

HP ProLiant server - PSU error despite replacing PSUs

We have a HP ProLiant ML350 G6 server causing us a few problems. The main symptom was that every so often we would find the server simply powered off. We turned the machine back on and investigated ...
turbonerd's user avatar
3 votes
3 answers
3k views

Does a higher-wattage PSU automatically draw more power?

Does a higher-wattage PSU automatically draw more power in comparison to a lower-wattage PSU even if the components fed by the PSU remain the same? The reason I'm asking is that I'm thinking of ...
AX1's user avatar
  • 1,289
3 votes
0 answers
58 views

Preserving a mothballed system: soft shutdown, PSU off or unplugged entirely?

I've got a system that looks like it's going to be kept around "just in case" (virtualization has already been explored). Long ago I had another such system but when when it needed to be ...
David's user avatar
  • 1,293
2 votes
5 answers
3k views

FreeBSD determine if reboot was due to power loss

We are running FreeNAS (which is built on FreeBSD) to run our data storage systems. It is running on an APC Smart-UPS 750VA X. On a couple of occasions, I have been alerted to the fact that the ...
Chris's user avatar
  • 1,289
2 votes
4 answers
15k views

Why do servers have 2 PSU?

I have a Dell PowerEdge 2900 server and it has 2 PSUs, so: Can I run the server by having only one PSU plugged in? I am not going to have this server on all day and night. I'm just using it to learn ...
Eric's user avatar
  • 112
2 votes
3 answers
6k views

How do I get the power consumption of a Supermicro server on the CLI?

How do I get the power usage of a Supermicro server from the command line?
Onnonymous's user avatar
  • 1,104