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Yesterday I received a second-hand Dell PowerEdge SC1425 1U server.

The cooling fans are extremely loud and I would like to know if there is a way to slow them down -- I searched Google but wasn't able to find any information on controlling the fan speed, and there doesn't appear to be a fan speed option in the BIOS.
My server also does not have the Utility Partition (F10 boot option).

Before booting while the system is showing the Dell logo the fans are slowed down, but once the system boots they seem to go to maximum speed.

I don't know if this is important or not, but the system has 2x2.8GHz Xeon processors, 8GB Ram, 320GB HDD. The BIOS revision is A03, and the image below shows the fan speeds reported by the IPMI sensors.

enter image description here

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Yes, the fans in Dell 1U servers are loud. – Michael Hampton Jul 29 '12 at 3:24
do you know someway to control it? – 01001110 Jul 29 '12 at 3:26
My first thought is something like this. But you will want to wait for a real answer below. :) – Michael Hampton Jul 29 '12 at 3:27

The fan speed change during startup is normal -- All modern servers start with their fans at or near minimum speed, run them up to full speed to verify that the fans (and their speed sensors) are functioning, then set them appropriately according to the measured system temperature.

The fan speed in a PowerEdge SC1425 is entirely controlled by temperature sensors (unlike the other servers I believe the "PowerEdge SC" series has no BIOS option to set/override the base speed: You're stuck with "automatic").

Note that if a sensor fails (or the system THINKS it has failed) the fans will run at full speed (this is a safety feature to prevent your server from overheating). All you can do is check the system event log to make sure there are no temperature sensor failures reported.

Also note that the fan speed profiles are determined by the version of the BIOS you have installed, so make sure you have the most current BIOS for your system (check the Dell website).

If the sensors are all functioning and you have the most recent BIOS your system is Working As Designed.

As Michael Hampton pointed out, 1U server fans are VERY LOUD (all of them - not just Dell) - they have to move a huge volume of air as the CPU heat sinks are typically behind the hard drives, which themselves generate a considerable amount of heat.

Since you're not supposed to be in the same room as the machine while it's running making them quiet is not a major design goal.

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Well if i got your answer, u recommend to move BIOS on A00 version, where have fan settings? And yes, for now the server will be in my room. If you see my picture from everest fan 3A & 5A are fault, for now i have no $ and time to buy new and i think to solder the yellow wire from 3A to 3B and 5A to 5B, some like bypass and the temperature/sensors system will think everything its OK- right? – 01001110 Jul 29 '12 at 3:55
Use the most current BIOS available for your system (check the Dell support site). I do not advise modifying your system's hardware to attempt to bypass cooling safety functions -- this may cause your system to overheat and damage itself. Replace the failed hardware. If this is a home system and you want to try unapproved modifications I can move this question to SuperUser, but any competent users there will tell you the same thing I just did... – voretaq7 Jul 29 '12 at 3:59
If you intend to run a server in an office or other space where people will be you really need to invest in a soundproofed enclosure - you WILL suffer permanent hearing damage from spending an extended amount of time around running servers, even just one. Soundproofed enclosures are NOT cheap... – voretaq7 Jul 29 '12 at 4:04
Yes its home server, move it if you want. There can be someone who can know about masking the system sensors. But my general question is there way to control it from BIOS or BMC or other. Current installed BIOS version is A03 and he is latest.\ – 01001110 Jul 29 '12 at 4:05
You can download a CD image with the same utilities that would normally be available in the Utility partition from the Dell support site (I don't remember exactly what they call it, but if you poke around you'll find it), but I don't believe you can set fan speeds on PowerEdge SC series servers -- the speed profiles are hard-coded in the BIOS (and if you have failed fans or sensors the system will run the fans at full speed no matter what the speed profiles say - again, this is a safety feature.) – voretaq7 Jul 29 '12 at 4:09

You can add water cooling, then remoive all but the fans in the power supply. Then add some 5 watt power resistors inline with the + to the fans in the power supply..

the supply ramps up current to the fans as it heats up so if it gets hot the fans will crank up enough to cool it off.

The sc series dont give a crap about the fans.. mine has been like this for months and I use it in my recording studio, it runs almost silently.

I did the water cooling with an old pc cooling radiator/fan, some clear plastic host from home depot. a bunch of fuel injection clamps. and 2 copper water colling blocks from ebay.. they are hose barbed and 40mm x 40mm.. I used the plastic heatsink mounts and the fan mounts as a clamp for the water blocks.

its a great machine and is almost as powerfull as my apple g5 quad, it can render the same file in after effects about 2 minutes slower than the g5.. It makes alot less heat doint htis kind of work thhat the powerpc..

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That's not a very helpful answer. The question was about controlling the fans, not replace them. – Thomas Berger Mar 4 '13 at 13:52
Who said anything about replacing the fans? Water cooling is not fan replacement.. it's fan elimination.. and if a near silent server is the goal, how is that not helpfull? – wildman Mar 7 '13 at 16:43

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