p870tm 2nd CPU fan port!

in this case i think it'll work just fine we if power it off primary 12v pin. 2nd cpu fan will just be at w/e voltage primary cpu fan runs at and both be controlled. i'll try grabbing two fans and test what is the maximum output of that pin if its 0.7A. (how did you figure out 0.7A btw?)

a 0.24A, 0.15A and 0.1A 12v fans would work for these i'll try splitter them.

 

"Output current limit" section:

 

in this table, with current short circuit protection at 0.2A, does that mean we got 0.2A more room to work with ontop of 0.7?

 

No, it means, that after short circuit protection is triggered, IC will start limiting output current to 0,2A max. With this limit fan will still works, but with much lower speed. If IC recovery procedure after fault will again trigger SCP, cycle will looped and fan will be continously switched between normal speed and clamped speed.

 

Can confirm this.

Also I would strongly advice not to run it on amp limit unless you feel like trying to break something.

 

would a shutdown/restart break this cycle? (i'd assume so)

i'll get something with theoretical value of say .15A + original CPU fan of .5A. combine the two, run them with FN+1 and see if i can get this triggered, if not i'll go up a tier .19A and then .24A fans.

my understanding is even though the fan is rated at .5A it might not draw .5A even at 100%, some might be +/- 5 to 10% or some might draw less than what its specified., no way to know until fan combination are tested.

 

Only way to figure out real behavior is checking this in practis.
Your method looks good, I'm waiting for results.
In my experience most of fans draws significantly less current than producer declares on label (e.g. 5V/0,5A fan from Clevo D870 draws 0,33A at full speed), so there's a big chance than second fan will work without any problems.

 

If you stick to ratings everything should be designed with some tolerance. The further you stray the more you will have to manually watch values.

 

It's true. For mass production designers assumes typical values in their projecs. But if enthusiast in his home is ready to spent a lot of time on testing solutions, there's possibility to achieve results much better than in regular device. Simple example - extreme overclockers. They selects processors, mainboards, powers supplies to achieve results far beyond regular user capabilites.

 

time to order the 12v fan boys (pun intended), i'll let you guys know how it goes once i got fans and splitter. fans are from china so this could take awhile.

 

The fan on the right. Did it fit and did it work? What are the part numbers? Thanks

 

it doesnt fit as nicely as the one on the left in terms of the fan part itself but the 4pin head fit nicely, left fan has pin issue the pin hole being too small and together. both these fan need wiring re-route so neither is plug n play. right now i still have the left one in the machine because im waiting for 12v fan, and additional wire/JST pin heads to do splitter.

right fan is this on ebay https://www.ebay.com/itm/282590636507

 

this is one powerful fan. https://www.ebay.com/itm/401308899604 sadly uses too much current, worth a try tho

 

If it draws too many amps you risk trying your motherboard.

 

unless you try to kill your mainboard you shouldnt ever buy that thing

 

Or have a power circuit drawing from something more substantial.

 

i could get an additional source, for example from all other fan slot. also 1.1A is what it claims rated at, use it in a desktop and find out just how much it needs at full RPM. probably stronger than the clevo fan for sure.

 

I know i'm going through an old thread @ole!!! did you ever find out if a fan worked properly in that slot, Plug and play so to speak?

 

I'd like to know, as well

 

Yes, it works...
http://forum.notebookreview.com/thr...ounge-phoenix-4.809589/page-331#post-10941647

 

thanks, papu

 

So the 4th header on the p870tm1 has actual power running trough it, and will power a 5v fan. However, the fan has to be correctly rewired, as the 4-pin header on the mobo does not use the standart pinout as pointed out earlier in the thread.

If you plug a standart 4-pin fan to it without rewiring you might blow you mobo as some people have in the past.
Here's a good thread to read up on it.

@aarpcard used a Delta BSB05505HP-SM 5v fan. I went with a slightly thinner Sepa HY60Q05AP 5v.
Delta fan is ~8-10mm thick depending on where you measure it, while the Sepa fan is 5mm.

You want to leave pins 2 & 3 unterminated, only using pin 1 and 4 to power the fan (+5v and ground).

This will make the fan run 100% always.

 

I would advise not getting a whiny fan.

 

You wont notice that with fn+1 anyway.

 

https://www.laptop-coolers.com/lapt...2kVRr4E5sIL3fLsCcsUBNZTl5p5sdQZxoCGnIQAvD_BwE

any ideas on this fan? seems to be in spec

 

Different frequency of noise, you will probably notice it quite a bit as a discordant tone.

 

Problem would be the height, you want something around max 8-10mm tall and around 6-70mm in width, if you plan on fitting it into the chassis with the back cover.

 

Extra height would also he wasted ad the fon stack is only so high.

 

Hmm, going to try something similar on my Ranger I think. I have a 12v fan already, would just need to make sure its appropriately wired for a desktop pinout.

I can then use my other heatsink idea for my GPU.

 

I'd discuss over at the alienware section regarding where to power it from.

 

I would likely power externally, I have one more 4 pin pwm connector on my fan controller

 

Ah you are going for a non mobile laptop.

 

It's basically a DTR now anyways, I have the t440p for anything outside of gaming.

 

It gets a bit hard to justify it vs a good mini itx system at that point for me.

 

Sure, you can build an ITX system at that point. But this is re-purposing older hardware for a new use.

 

ITX are a pain to travel with internationally.

 

so finally stopped procrastinating and finished it.



doing both fan at 100% with software is fine. but if i use fn+1 it will trigger that protection and both fan will stop spinning and revert to auto profile, so unless I find another fan that works with fn+1 or i just dont use fn+1 then should be good.

another interesting find is that the added grill on CPU heatsink that doesnt exist pre 870TM models, actually has higher temperature than primary radiator.. this might be because of higher IHS/pressure from the 9900ks over 8700k. so now replacing the old 5v fan with 12v fan thats controlled by machine should work wonders.

now only need to work on the mount and/or find a new fan.

other mods, too lazy to post in other forum section. need to add mounts for optane as well and get a heat pipe with thermal pads to middle fan for cooling.

 

The new part sits over the VRMs that run hotter than the CPU.

 

not with 8700k. tested with that and it sucked hard. but all those dont matter cause next one is gonna be bare die cooling hope i dont crack my cpu die.

 

anyone knows that these rubber/stands are called? need to buy them for heatsink mod but no idea what they're called. @Mr. Fox @Papusan

 

Foam or rubber with glue on one side

 

i'd probably have to start from there lol but better than nothing. thanks

 

Try square rubber feet/bumpers https://www.amazon.com/square-rubber-feet/s?k=square+rubber+feet

 

It will be to stop vibration between the casing and fan so anything will do if you want to out something there.

 

You can try do add PTC thermistor in series with second fan. This is common method to reduce current spikes during startup in power supplies. I think a value between 4.7 and 8.2 ohms would be good.

 

i could do that, just that i think reason fan profile 100% being actually at 80% is to protect fan longevity so I am fine without using fn+1. also tbh with fn+1 is rendering machine unusable anyway as it is too loud. I also got another stronger fan with more CFM and much more capability with air pressure thats coming while using less amps so i'll check that out once that gets here.

@jc_denton @Papusan spent about 8hrs getting learn using tools and reading manuals etc. special thanks to @Mr. Fox recommendation of tools on where to buy them and to use it in his soldering shim vid.

Spoiler

View attachment 182899

so after separating the fan from heatsink and solder that VC to heatsink got that. look at the picture with red vs green box. green is fine theres no space/gap so it's pushing cpu pcb down to contact with socket but red theres spacing and computer wouldn't boot cause of it, seriously thought i killed my cpu till i put it all back with IHS and seemed no problem.

theres these little resister? capacitor? transistors? w/e they are are pushing up rockit cool die frame. I need to shave away bits off the die frame and that'll be task for tmrw. once thats done i hope theres not too much pressure on the die or it'll just crack.

 

Looks like you will need to dremmel a channel in the plate.

 

thats what it is. dremel 3000 to separate fan from heatsink to begin with. except this direct die frame is smaller and has less room to hold/cut and much more dangerous. dremel doesnt seem to come with metal shaving tool so I can only try to cut it.

 

You can get many types of attachments and a clamp/vice would work.

I used mine to cut through steel plate