Question Fans on constantly HP Z420

[blaze3000]

Hi,

Looking for any pointers. I have a HP Z420 8GB RAM running Windows 6 x64 from one 1TB HDD, CPU is Xeon E5-1620 v2. BIOS is HP J61 v03.91, which I believe is the latest (the HP online diagnostic doesn't seem to be working at the moment).

Ever since I've had it about 5 years ago, it has been really loud - I can hear the fans over the volume of music through my headphones. The fans seem to be on constantly, even though the temperature seems to be well within normal range. Using the CoreTemp tool it indicates all CPU cores around 40-50 degrees. My typical usage is just web browsing, so CPU use is low with high physical memory use according to the task manager. I notice other users say that this machine is low noise, and that the fans are sometimes noisy on startup and then subside, however mine just stay on all the time, there's no variation or power up/down noise during use.

I've gone through other guidance to adjust the power options (change advanced power settings> power saver> sleep> sleep after / hibernate settings) which haven't made a difference.

There weren't many programs running on startup or in the background, but in any case i've culled them. So now I only have Microsoft security essentials, Intel Rapid Storage Technology and Intel Management and Security status running in the background. That hasn't made a difference.

Looking inside the case, there are three fans running - the main CPU one, the one on the rear of the case, and the power supply one. There are two other fans in the machine which aren't running constantly - the one on the graphics card, and the other one over the heat sink.

Super grateful for any pointers on where to look. Presumably this is something to do with whatever is controlling the fans? I haven't actually had any issues with running the PC at all, apart from it being really noisy!

Thanks

 

[Paperdoc]

Look at the workstation manual here

http://h10032.www1.hp.com/ctg/Manual/c04205252.pdf

Top of p. 48 it says you can alter the minimum fan speed for low-workload operation. This may affect the CPU cooler fan and / of the rear case fan. It will not impact the PSU fan.

 

[blaze3000]

Thanks!

So I just went through the menus in the BIOS and under 'thermal it had 6 pips which turn into squares when you dial it up. I set it half way, and the PC was much louder So it was already set to the minimum. I guess that means this is just a very noisy machine at idle?

 

[Paperdoc]

Another thought. As old fans wear out their bearings and create extra clearance between bearing sleeve and shaft, they "rattle around" in the bearing and get very noisy. At first this happens only when starting up from cold. They warm up from running and the clearance reduces and the fan goes silent in a few minutes. Stays quiet until it is off long enough to cool down. You have noted reports of this by others. As wear continues the noisy start-up period gets longer until it is constant. Eventually the fan seizes up - terminal silence! The only cure is replacement of the fan. Any chance that it your issue?

 

[blaze3000]

I'll be honest, now that the weather has cooled down a bit here the noise is not as bad. I'm hoping that's not just my perception at play, the fans are still on but not making as much noise. The readings from coretemp are much lower too - with the range usually in the 30s.

Thanks for the thought though, I would be worried if there were no noise for sure. Not sure about whether the bearings are getting worn. I would consider preventatively replacing them, but my guess is that the noisiest one is in the PSU - my technical ability is not so great, so i would do more harm than good trying to get that out!

 

[Paperdoc]

Agreed. It is unfortunate, sometimes, that the FAN in the PSU fails while the rest appears OK, but you feel you have to replace the entire unit. I've done the fan replacement job, but I am quite "handy" with repairs and simple electrical circuits. The fan inside typically is just like a simple 3-pin fan for a computer case, but of a particular size, and often with non-standard connectrs on its wires - or even soldered in place. So you do need some skills for that AND you need to know how to remove residual electric charges in capacitors to render the innards of the PSU safe to touch. NOT a task for a beginner.