HP z420 workstation fans loud after GPU upgrade

[Davidross0904]

UPDATE 11/18/2020: I rephrased everything since it looks like the original post is very confusing in terms of everything, as i was in a rush at that time. I hope it is a little more clear now about the problem. I posted this because I couldn't seem to find any other effective post that actually solve the problem when searching online, so i think that this is a perfect time to address this issue I had with this workstation, and even help others with the same problem fix it in a concise way.

Hi everyone,

So I did a recent GPU upgrade on a old HP z420 workstation, which i got during a company moving sale for like 160$ US. it had a old  Quadro K2000, which i upgraded to an Asus TUF - GTX 1650s, which provided a performance boost of like 6X the original card. It's perfect performance wise, however the fans (especially the rear fan and PSU fan) all run way louder from before and the case fan now runs at 1500RPM compared to like 600RPM, according to the HP Performance Advisor which was recommended from the other threads for reading fan speeds.

I find the noise irritating especially since it used to run way quieter, but why would just a simple graphics upgrade cause so much noise? I even tried switching back to the old Quadro and it became as quiet as it used to, which shows the problem is most likely linked to the graphics card.

I even switched the fan to quieter AVC 3000rpm one with rubber cushions for acoustic dampening but still, very loud. Using low noise adapters only reduce the noise a little and not allows the fans to ramp up so the computer can remain quiet, and it is still noisy after all, and I had thermal problems where the CPU just goes above 80 degrees celcious. Is there any way to fix the problem, and not the symptoms? I also tried to downgrade the bios from 3.96 to 3.90 and still no change....

Possible fixes:

-Use Noctua fans (enough airflow? will it effectively keep the pc cool?)

-External fan controller controlled to ramp up the fans based on a custom temperature curve? Also add in fake pwm generators to prevent the f1 error of missing fans?

-have HP fix the problem (does not look possible as I have a void warranty)

My Computer Spec:

HP z420 Workstation (stock configuration, original cooler with new thermal paste, BIOS at 0.90 (downgraded thanks to a post about the magical green header) CPU/Processor: Intel Xeon E5-1620 0 (first version, no overclock)

GPU/Graphics:

ASUS TUF series  GeForce GTX-1650S (dual fan)

Old GPU: Nvidia Quadro K2000

RAM:

32GB (8 sticks of 4GB ECC DDR3 RAM)

SSD/Drives:

1 Samsung EVO 500GB SATA SSD

1 Silicon power 256GB SATA SSD

[DGroves]

when you changed the cpu..........did you go from a 95 watt one to the e5-1620 which is a 130 watt one?

if you did,.... have you also upgrade the cpu cooling to the high performance unit? or the liquid cooler option? if not then this is most likely the main reason for the fan speed/noise as it tries to cope with the major increase  in heat which the stock 95 watt cooler was not designed for

[Davidross0904]

I did not change the cpu in any way, other than adding new thermal paste. The cpu used to stay at like 70 degrees max,  but now it is hitting 80 degrees. Is there any problem to fix the fan problem also?

[DGroves]

as LCox1987 stated , if the cpu is reaching 80c then that's why the fans are spinning so fast trying to lower the cpu temp

either the cooler is not making correct contact with the cpu, or the cooler itself is defective

resolve the cause of the high cpu temp and you will also resolve the high fan speeds

[Davidross0904]

Yeah, I totally agree, i will be change the CPU cooler at some point. At boot/idle, it stays between 40 -50 degrees celcius however, and it only reaches 80 after running both a GPU and CPU benchmark at the same time. I also think another problem is the hot air having no where to go, and therefore heating up everything. However, the thing is that the fans run loud just around when the HP bios screen shows up, and does not speed down compared to before when it will become very quiet. So yeah, there are two problems, one being the CPU running uncomfortably hot and the case fans running loud

I also realized that the hot air from the CPU cooler is staying in the case, so I am thinking of adding large fans as a mod to the case. Do you know anyone who did so? I will try to get the Liquid cooler at some point for better cooling. Thanks Dgroves and LCox1987 for stating this issue also.

[DGroves]

no,..........your last post contained clarification............it's completely normal for the cpu to reach 80c during a cpu/gpu stress test

so 40c at power on idle is normal cpu cooler is most likely NOT THE ISSUE

the z420 has a ambient air temp sensor in the power cable that is known to fail you can test this by installing the HP Performance advisor app or checking the bios for this

https://www8.hp.com/us/en/workstations/performance-advisor.html

or this app

https://h30670.www3.hp.com/opensource/product.jsp?cat=1070&fam=Notebook+PCs&prd=openhardwarelib

if it reports 0c or 255c your sensor has failed and you either need to replace the cable or the failed transistor in the cable

[Davidross0904]

Ummm i also checked the sensor.  It displays 23 degrees in performance advisor. Covering the sensor does make the fans louder. It looks like the IDLE speed has increased after i have changed to the new GPU.  Is there a BIOS fix or mod?

I also changed the PSU fan from the old hp to now a simular 2000RPM one. It moves 45CFM but i am concerned about the PSU overheating. With the OG fan, the air from the back is cold. But during a stress test mentioned above, the psu has warm air but i dont know if it is the PSU generating heat (90% effecient) or is it just the CPU and GPU generating the heat and the psu moving the air out.

[nobleman2020]

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@LCox1987 wrote:

It seems to me that the problem you have is that the fans have to work harder to displace the additional heat, which of course is potentially harming your computer. If you want to keep it, basically you only need to add more cooling to the computer. If that doesn't work, well, I don't think I have a solution for you, and in this case, I would strongly advise you to talk to a specialist who might have some additional information for you. What do you use your workstation for? If I were you, I would take a look at https://canadamonitors.com/index.php?main_page=product_info&cPath=75&products_id=2299 because I suppose you use your workstation for games and they have some great workstations out there.

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Yeah, you're right!

[Davidross0904]

yeah, I am getting the cooler this Christmas. I am a 15 year old who is very interested in computers but does not have the money to finance myself lol. So basically I am getting 2 Noctuid A9s (one for the Rear case fan and another for the PSU), in which the PSU fan can be replaced easily, but I highly not recommend it because it is dangerous and only do so if you are a trained person that knows electronics safety, and how capacitors can shock you. 

For the cooler, i may get another noctua (perhaps one with 2 120mm fans) that has a large surface area therefore cooling the CPU effectively.

However, do noctua fans work with the z420? I heard that there are some BIOS warnings and popups requiring you to press F1 to continue boot, because i heard that they don't spin at 0% PWM. Has anyone had noctuas connected to the rear fan headers? did it throw warnings?

[DGroves]

many consumer and 3rd party cases are poorly designed for good or proper airflow, or might have cooling that is "just good enough" for the factory configuration(s)

workstations and servers are different in that the maker (HP in this case) will spend the time to test all aspects of a system including to make sure the system will run without thermal problems 24/7 over their stated temp range.

and in regards to workstations the vender also considers noise and tunes the cooling to rather low noise levels due to this it's rather hard to improve workstation cooling as just slapping on more fans or changing fans usually makes things worse

due to this HP workstations are rather quiet even at full cpu load with all options installed inside the case

because HP uses fans with a custom cooling speed that matches the bios cooling curve settings, replacing the fan(s) with different ones (even noctua) will usually cause a rise in the case thermals and/or no improvement in noise levels

you might want to read case reviews from sites that do know how to test case airflow and fans, one such site is "gamers nexus"