I am not certain higher voltage fan such as 12V fan would necessarily provide better cooling than 5V fan in Dell micro. It is the cubic feet of air (CFM) it can move that matter. The cooler in micro is blower type.  One example of Foxconn PVB070E05N fan in micro spec is 5V 1.10A 11 CFM.    Another example of Delta fan ksb0705hb-a in ##40 Micro has about the same spec.

This other 80mm FoxConn fan PVB080G12H (12V, 0.6A) spec is 18 CFM.  This is a blower type fan used in Dell Optiplex 9020 SFF which has a 12V fan header.  Trouble is you can’t connect a 12V SFF fan to Dell micro motherboard that has a 5V fan header.

Hi redxps630, thanks for the replies.

When I comes to your comment that the higher voltage 12V fan would not provide better cooling than a 5V version, I beg to differ. (Sorry, not trying to win an argument here, just trying to crawl out of the rabbit hole I have found myself diving into)

When looking at my Dell Micro 7080, the fan code is Model: KSB0705HB-A, DPN: JV47V-A00 (5V, 1A) and produces a CFM of 9.8CFM.

On my Dell Micro 7010, the fan code is Model: EFH-07C05D-CP01, DPN: WYT09-A00-A00 (5V, 1A) and produces a CFM of 11.5CFM.

I have seen other 5V models, example fan code Model: PVB070E05N-P02, DPN: JV47V-A00 (5V, 1.1A) which produces a CFM of 12.69CFM. (Note that this one takes 1.1A but produces 30% more CFM than the one in my Micro 7080 and 10% more CFM than the one in my Micro 7010) There are a few more like this and there are too many to mention.

(This itself shows a variance in the 5V versions.)

When looking at a Dell Micro 7080 12V versions, an example Model: PVB070E12H-P01, DPN: 0C5T4N (12V, 0.95A) which produces a CFM of 14.20CFM. (Note that this one takes 12V and less amps at 0.95A and produces 45% more CFM than the original 9.8CFM version) There are also versions that take 1.1A and produce even more CFM.


At the end of the day, i'm wondering if I can slap a 12V version on my dell micro and maximise my cooling. This may not be important to people but i'm just curious and have already gone so far down the rabbit hole, I might as well try to get an answer.

Yes I find a few 12V Foxconn blower type fan having significantly higher CFM in spec (many 12V fans omit to mention CFM on sticker).  here is a longer answer from a senior EE engineer 

“the rated voltage of a fan motor does not in and of itself determine how much air is moved. The amount of current drawn and the design of the impellers has a large effect as well. So two fans both 1W and equipped with identical impellers turning at the same RPM but one 5V and one 12V, will be for all purposes equal in performance. Changing the motor to run faster or the impeller design to push harder will change the relative power. The amount of current drawn and hence the power (VxA) will depend upon the impellers and the air flow resistance presented.

P.S. Given same size and type of fan, the critical items are now the CFM, the impeller design and the RPM and power of the motor.

Assuming that we have designed the fans with the same RPM motor and same impeller design, then the fans should move identical amounts of air and cool identically. The power consumed to move the same amount of air should be close to the same, so the 5V fan will draw about 12/5 times as much current as the 12V fan netting the same power consumption.”

I understand what you are saying.

But, at the end of the day, I still don’t have my answer.

1. Can I change the 5V cpu fans to 12V units with higher CFM.

2. Do the Dell Micro boards support 5V only or are they able to support 12V fans also?

3. Will I spoil the board or fan if I just hook up a 12v fan.🪭 

I appreciate user interesting question and feedback. Thank you for sharing the info on 12V blower fan PVB070E12H-P01  in some Optiplex Micro such as https://www.ebay.com/itm/335353507711

12V 0.95A 14.20 CFM

I think I find some answer here

7070 M cpu is 35W

https://www.europc.co.uk/pub/media/specs/dell-optiplex-7070-specsheet.pdf

7080 M cpu is either 35 or 65W

https://www.hardware-corner.net/wp-content/uploads/2021/02/dell-optiplex-7080-datasheet.pdf

hence Dell designed 12V 65w more powerful higher CFM cooler in 7080.  There is still 35w cooler offered in 7080 (D10) too for 35w cpu.

Here comes interesting 

7010M cpu is all 35w.  Reason why Dell reverted to 35W cooler

WYT09 ASSY,FAN,BLWR,MFF,35W,HF

https://www.delltechnologies.com/asset/en-us/products/desktops-and-all-in-ones/technical-support/optiplex-micro-spec-sheet.pdf

but, but if you have the higher end Micro Plus 7010, cpu is mixed 35 or 65W you can bet Dell uses 12V cpu cooler (e.g., Dell X7Y1H) for 65w cpu in that model. Unfortunately like I said before different motherboard is designed differently. It is risky to use 7080M 12V cooler in 7070M, and like so risky to use 7010 Micro plus 12V cooler in 7010M.

“Final” thought as I come out of the rabbit hole following the white rabbit aka OP just kidding, there is hope. If 7080 35w and 65w cpu motherboard are identical then it is ?possible to exchange 35w cooler for 65w cooler or 5V for 12V?  Both coolers offered in 7080.

Still not sure of using 7010 Micro plus 65w cooler in 7010M since it is a totally different motherboard 

This is a high risk but possibly? good return adventure I would not recommend but some brave user might experiment 

Alas on further investigation 7080M motherboard is different for 35w vs 65w cpu therefore at the end of day unfortunately you cannot use 65w cooler (12V) for a 65w version motherboard on a 35w version motherboard even though both are 7080M

makes sense. I have not heard of a fan header that can be versatile to work w both 5V and 12V fan. 

I realized today there are 65W cpu in 7070M too.  I wonder if there are different 65W motherboard version in 7070M too.  and turns out Del has been doing this thing for a long time (two versions of mobo: 35w vs 65w)

here Dell also designed different voltage fan for the two motherboards which are not interchangeable.

7070M