XPS 8940, Better 3rd party cooler

Actually the Vetroo V5 is really quiet! When system really heats up for benchmarks its the OEM rear fan that I hear roaring! Yea I'd def like to know how the additional other fans contribute - all your fan additions easily add up to close to almost $100! It's a slippery slope with upgrade-itis 

@EhsanHaque24 

SA Akhi

Your plan for the NA-FC1 is correct and absolutely better than using the y-splitter.  The amount of power via the header is constant and determined by the BIOS.  It is not meant to power more than one fan.  You will most likely under power the fans if you were to use the y-splitter.

Everything else you stated is also correct.  It seems that you have a good handle on everything.  If you are looming for my recommendation then I would say to install the NA-FC1 and use it to control the front fan and the CPU fan, or fans if you have two on the CPU cooler for push/pull airflow.

I do have the Noctua NA-FC1 in my PC.  Essentially, I wanted to accomplish two things with the NA-FC1.

1 - Add more fans to the CPU cooler to achieve push/pull airflow.  Darren_F has a good picture of this configuration on page 8 of this thread,

and

2 - Take advantage of constant higher rpm (No-stop mode) of the Noctua fans via the dial controller on the NA-FC1.  The NA-FC1 will allow you to override your motherboard’s fan speed threshold that are determined by temperature and set by your BIOS.  So, for example, if your CPU is running cool then theoretically you are below the temperature threshold and therefore the BIOS would tell your motherboard to decrease fan speed to CPU Fan.  However, CPU fans such as the Noctua 92 mm do not take that much power, hardly any to be honest, so any heat they may produce while running at higher rpm is completely negligible, and so minute as to not have any impact on any of the temperature thresholds in your PC case.  My point is that there is not any drawback to running the fans constantly at higher rpm via the NA-FC1 No-stop Mode.

The YouTube video below has a great explanation and demonstration of the NA-FC1.

https://www.youtube.com/watch?v=LZuxvv7G4fw

I actually installed two NA-FC1 Fan Control units inside my 8940.  One is controlling the two fans attached to my Noctua CPU cooler and connected to CPU FAN header, and the second NA-FC1 is controlling the rear fan (also changed to Noctua) and connected to the SYS FAN header.  I am operating both NA-FC1 in No-stop Mode, so all fans are always constantly running at full rpm capacity regardless of the temperature in my PC.  There is an extremely low humming from the fans, but I am being very honest when I say that I can only hear it when I get close by putting my ear to the front of the case.  Again, it is not noticeable and certainly not annoying or disturbing, at least to me it is not noticeable while I am using my PC.  My PC is below my desk on a rolling stand about five feet from my head.  I imagine that you might notice it if you had the PC on top of your desk and directly in front of you next to your monitor.

When mounting the fans ensure to follow the arrow direction that is clearly marked on one of the Noctua fan sides.  All arrows should point in the direction of the desired airflow.  In our situation with the 8940 case that direction would be internally from the front of the case to the rear of the case.  In other words, all the arrows should point towards the rear of the case.

The NA-FC1 Fan Control units should be powered by one of you SATA power cables inside your PC to have sufficient power to run multiple fans (up to three per NA-FC1).  I had to purchase a SATA Power Splitter cable to connect each of the two NA-FC1 Fan Control units to one of the SATA power connections available within my PC.  Here is the splitter that I purchased.

https://www.amazon.com/gp/product/B00V6QA65G/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

I know that this might seem like overkill to many, while others might be intrigued by it.  Nonetheless, I hope that this can help you and those that might be interested in this endeavor.

Below are my temps with both NA-FC1 set to No-stop Mode for all three fans.

40 c – While Idle (Almost nothing is open other then CPUID HW Monitor for reading temp that I manually started, and some background processes at start-up such as Norton, etc.)
42 to 66 c – While Web Browsing (10 – 20 tabs), MS Office programs (Outlook, Word, Power Point, etc, to include Visio), several other programs open such MS Teams, etc.

51 to 80 c - While gaming

Regarding moving the front HDD cage.  I have two 10TB HDD in my PC, so therefore I needed both HDD cages.  With that said I do not have the space to place a fan in the front on the inside of my case for even more airflow.

Lastly, here are my specs

• i9 10900
• Crucial Ballistix 128GB 3200Mhz DDR4 RAM (4x32GB)
• Nvidia RTX 3070
• 1 x Samsung 980 Pro 500GB SSD (OS and programs)
• 2 x WD Black 10TB HDD in RAID 1 (Docs, pics, videos/movies, music, games)
• Noctua NH-U9S CPU Cooler - CROMAX Black version
• 3 x Noctua 92mm fan - CROMAX Black version (two on CPU cooler and one on rear)
• 2 x Noctua NA-FC1 Fan Control Unit

@mybuddie which cinebench were you using, R15 or R20? I'll try to run some quick tests step by as I upgrade this second 8940 for my co worker this week.

As for the costs, yeah it's a bit much maybe but I like cool and more importantly quiet. Normally I build my own PCs but with the availability of parts what they are, and the admittedly nice size and form factor of these 8940's I'm keen to spend a bit of extra cash to make any pre built as good at they can be.

Even with the PC's I have built I've spent some decent cash on fans to keep things quiet and cool so an extra $100 is worth it imo although honestly just upgrading the poor CPU cooler and moving on is probably the only real requirement - the rest is maybe just for fun but that's worth something! haha

Also does anyone have a link where the Vetroo V5 is reasonably available in Canada? I'd love to try it, but the best I can find is like $40 + $25 shipping on Amazon.ca or trying a random ebay seller

Believe I’m using R20. Yea quieter is definitely worth something, knowing that the noise is mainly from rear case fan I’m apt to move 92mm noctua fan from old desktop to this one, hoping it’s indeed much quieter. That fan didn’t seem to do very much in other system anyway. Yea with upgrades or any purchase just gotta be clear what you getting out of it. I lean more practical side than for aesthetics or hobbyist pleasure, though there’s nothing wrong with that if that’s what you like. There’s always a crossover point from where somethings good bang for buck to what’s just gravy 1-10% gain for 50% more cost. Like I’ll be getting G5 system with i3 and 3060ti... totally bottlenecked but I’m struggling with idea of upgrade to i5 for a marginal performance gain. Also kills the warranty 

@mybuddie agree 100% on all counts!

Since you removed the pancake CPU cooler, something else worth thinking about is swapping the stock rear case fan with the stock CPU fan. They are both 80mm I believe but they aren't identical in my system - the CPU fan I believe is 7 blades vs the 5 blade rear fan and may run quieter.

For anyone wanting to know, ran both the exhaust fan and cpu fan on a 360W PS with a 35C delta in max temp.

Swapping the two 80mm fans may not be a good option.  The one on the rear panel will be specified for air flow, whilst the one on the CPU cooler will be specified for air pressure.

Definitely a valid point, but would only take a couple minutes to try out. Note that I would not necessarily put the case fan on the CPU block; I'm assuming the CPU cooler is upgraded. As an odd side note, I did an update and restart last night prior to trying some temp testing and for the first time the PC threw a fan check/error on startup on the SYS_FAN. This is really odd as it hasn't done that up until now with the A9 and A12 both plugged in using a splitter (4 pin to the A9). I will do some more investigating tonight

@mybuddieI ran some rough tests last night and have a couple more planned today but so far I don't really have any evidence that adding the 120mm fan to the front does much of anything. I have a feeling the front fan gets throttled by the bios PWM of the rear fan so I want to try swapping the splitter. What is clear IMO is that upgrading the rear fan to the A9 is a definite improvement to both CPU and GPU even with the stock cooler. Interestingly, with the stock pancake cooler the case seems to work better under negative pressure (single A9 at the rear, no intake) and not well under positive pressure (single A12 at front,no exhaust)

anyway a 120mm fan can be mounted to the rear? 

@EhsanHaque24 

Your notes on the picture are correct.  I do have one question though.  The NA-FC1 in your pic only has connections to power two fans.  Mine has connections to power three fans.  Did you cut one of the fans connections off?

I'm just starting the cooler upgrade journey on my XPS 8940 (i7-10700 (not K), 16GB (2x8GB), RTX 2060, 500W Chicony PSU).  I bought the computer about 6 months ago as a quick replacement for my XPS8900 that had stopped booting (now repaired, failing HDD cloned to 1TB SSD plus new HDD).  Both computers are now running in different rooms in my house here in UK.  The cores on the i7-10700 have been running much hotter than those on the i7-6700 in the XPS 8900.

From 24 hour continuous running of HWMonitor, I'm getting minimum core temps of 13°C-14°C (55°F-57°F) on the i7-6700, but minimum core temperatures of 33°C-35°C (91°F-95°F) on the i7-10700 in the XPS 8940 (unmodified).  The ambient temperature where the XPS 8900 is located tends to be lower, but not by that much.

I had a spare Arctic F9 PWM and some Akasa fan mounts sitting on the shelf left over from a recent computer build, so last night I replaced the 80mm exhaust fan with the 92mm Arctic fan.  I also removed the top HDD caddy and moved the HDD in its caddy to the top position; I needed to replace the SATA cable as the one fitted was just too short.  This has dropped the minimum core temps down to around the 28°C-30°C (82°F-86°F) mark, with running temperatures when surfing the net, reading emails, etc. around the previous minimum temperatures.  Overall, I believe I've achieved a 5°C reduction in core temperatures from changing the fan, etc. during normal computer use.  But I'm not down to the core temperatures of my XPS 8900.

The first thing I notice is that the Arctic fan is definitely louder.  I'd like to confirm that the fan is actually running in PWM mode and not flat out.  There's nowhere in the BIOS where I can check this, nor have I found any software to let me read the fan's speed.  I've tried running SpeedFan, but not only can't it read the speed of the fans, it can't read the core temperatures correctly, either.  HWMonitor, Speccy and HWiNFO64 all agree, but SpeedFan gives completely different readings.  Does anyone know of a software tool that will let me see my fan speeds?

Thanks to purpledrillmonkey, I'll be taking delivery soon of an adaptor to allow me to fit a 120mm fan at the front of the case in the space where the HDD caddy was.  The adaptor is costing me £6 and will be made in PETG which is better with heat than PLA.  I'll be able to see if this makes things any cooler.  I've four spare 120mm fans, three 3-pin and one 4-pin PWM and will be trying one of these in the case.

Living in the UK, my computer doesn't experience the high ambient temperatures that some others do and I'm not a gamer but I'm concerned by the temperatures my XPS-8940 has been reaching.  I'm looking at different CPU cooler options and wonder if anyone has fitted the Arctic Freezer i13 X CO in their XPS 8940?  It's designed to handle up to 150 W thermal design power (TDP) and the i7-10700 is rated at 65W TDP, so should easily handle it.  Also, the installation looks straightforward, with the spacers screwing directly in to the Dell cooler mounting points.

@Tarak Abu Adam 

Salaams,

Thank you for getting back to me and for confirming and answering my questions.

The NA-FC1 has connections to power 2 or 3 fans, I just chose the cable (that came from Noctua) to power 2 fans instead of 3 fans. I am assuming that is what you mean? I would never cut anything like that, haha. 

Serious question.  Are we sure that the stock rear fan on the XPS 8940 is PWM?  It looks to be, with 4 wires, but  looks can be deceiving.

The stock fan on my XPS 8940 is Delta Electronics Inc. DC Brushless fan AUB0812HHD rated at 12V, 0.40A, Dell P/N D4NJ4-A00. Nowhere on the fan does it say PWM, or anything similar.  Is it possible that the two extra pins are being used to check for 'fan not present'?  I have pulled up the Delta Electronics Inc. data sheet on the AUB0812 series of fans and these are voltage-controlled DC fans, although only 2-wire.  The AUB0812HHD is listed with a voltage range of 5.0 to 13.8V, 0.32A and max. speed of 4800 RPM.  Delta Electronics Inc. do not list PWM fans amongst their products.

If the stock fan is DC, then this would explain why my replacement PWM fan is running at full speed all the time.

Has anyone connected the XPS 8940 exhaust fan to another computer and shown it to work as a PWM fan, or can confirm this another way,?

I started off to look at loading on the header pins.  The stock exhaust fan gives 0.4A, whilst my Arctic F9 PWM is only 0.16A and an Arctic F12 PWM is 0.12A.  All things being equal, the power draw of both the Arctic fans combined will be below that of the stock Delta fan.

So if I buy one of these pc's the l9-10900K will it come with the upgraded cooler already installed?