Topic: Hacking KNC Titan / Jupiter / Neptune miners back to life. Why not? - page 20. (Read 76853 times)

one erricsson VRM at titan board burn can anyone replaced it??

or is impossible?

Then make sure the fuses are in a reasonably cool location or derate fusing as needed (increase fuse size). That said - look around for thermal derating charts from Bussman/LittleFuse/etc so it is done right. The only downside to derating is that under cold starts the permitted current will be quite a bit higher...

Well, in the back to drawing board world I just dropped a couple of hundred bucks on a thermal imager. Want to see if I can find out more about where shorts are happening on these boards.

Never give up :-)

I think someone looked at those once and they blew often due to heat lol 😄 The auto fuse anyway idea

Likewise my one recommendation would be to put a 30 amp automotive fuse in line to each Titan from that big supply. That way if a Titan shorts a capacitor it will blow the fuse before catching fire.

Actually a super idea would be to put a 10 amp fuse on each one of the three lines that feed each titan's PCI plug. That way if a plug line went bad the other two fuses would blow, saving the titan from the ground fault fail.

plenty dirty my cubes weren't they Likely MOST of my gain of 35mh on 700mh setup was due to the lack of dirt imho.

Then again not messing with the titans seems to work best in my case, but live an learn need to blow them out every 4 months or so etc

But man that 3000 rpm fan is great.....with the heatsinks ...big drop in heat....it is 88F in my basement humid as heck heat index over 100F

and my dc/dc's are hottest one is at 74c most are in 60c range yet ...lol For a miner that knc told me was 'supposed' to run in the 75c to 90c range
and could run to 100c ok...(yeah they really really wanted to justify overclocking to 325 at -0.366 setting in a big way not to RMA the beast)

it is a dang miracle imho from what I was doing to this poor abused group of Titans the last 22 months (ack! titan abuse)

anyway so far so good

likely to get MUCH better as I replace all the psu's with the 2560 watt dual psu hack and 15 awg wire to the cubes....ie NO ADAPTER NEEDED soldered at the other end
and cool to the touch. Less fail points. Also with the Gen Tarkin software set at 90c failure on the dc/dc's (gonna be damn hard to get there from 74c top end now in this
weather) I figure I'm covered.

Before ...when titans were dirty as hell and not repasted I was running 85c to 90c and the poor gen tarkin software was a toggling stuff up down all over the place
when it was over like 80F in the basement

now it is like 'meh' no issue with at worse 60/70c dies on a regular cool no humidity at say 78F in the basement with the Titans going ..heck most dc/dc's are in the
55c to 65c range...my hottest one is 71c or so lol

looks likely with these hacks we can extend these puppies for years yet w/o them going doorstop (knock wood)

edited: correction ---  Replaced dc/dc's for dies on the above as a pointed out correction.

Nice job! Yes, the rubber heat transfer things get yucky, I can clean them with isopropyl. Remember to remove all the heat sink crap, even a crumb can press into the chip and break a die.... I use 95% isopropyl.

I like the heat sinks on the PSUs. Beautiful work....

Nice results! =)
Id probably tinker w/ my Titan but its hosted up in Alaska. My buddy up there blows the cubes out w/ an air compressor every few months. Completely stock configuration. Been running perfect since he received the Titan new back in 2014 , well there was one time where the PSU side of one cable melted ...but that was due to a crappy connection on modular PSU cables =/
The cubes themselves show no signs of heat wear on their power ports.

Well on to my OTHER project I just got done.

I have revamped ALL my cubes ..this is a complete repaste/3000 rpm fan/copper heatsinks/Maxumark X bracket replacement and cleaning of cubes. This was 10 cubes total for
me so far out of my 14 cubes. The cost was about 60 bucks a cube but well worth it imho for the temp drop on the dc/dc's alone.

here is a link to all the parts and the best prices I could find on such..the last 3 months as I accumulated the stuff needed.

https://bitcointalksearch.org/topic/m.15286157

Also helpful these Swedish Videos on youtube. The parts I used were the same as he said to use in comments. My sources are cheaper however in above link. Note: the
video in Swedish has more detail and more complete. The 2nd video below in English has less detail. Watch both.

https://www.youtube.com/watch?v=O-RBI4am-wY

https://www.youtube.com/watch?v=-G_zcJ0vbOw

Finally got around to cleaning my cubes...they was beyond dirty....I have lived with these 'evil' machines by treating them like cats.....as
little attention given by myself as possible..and as a result they don't sulk and don't try to brick themselves at any possible perceived slight when I make inadvertent eye contact doing laundry or something..they are 'evil' I tell you (tm knc)

(hey we are all a little crazy to mine crypto.....if I want to think that they are the equiv of a bad Steven King novel in a Christine like an evil asic miner processed kinda deal ..well wth)


Well it worked for 22 months...then I had a power plug go real hot to the touch. It looked fine...but would not pull off...melted in a blob inside.....as a result I looked into the cube and this was what I saw below. See my full setup here if anyone is interested. lostgonzo.imgur.com Thus have the bare pin mod (now on 2 cubes) works fine no issues, just saying. But it got me off the fence to re-do the cubes. Don't be me. Get to this stuff soon.



Ack!

So much Q-tip and alcohol rubs later on the Titan cube board along with a repaste using the the previously mentioned complete revamp of the cube I have had the following conclusions.

 
1) you probably should at least blow out your cubes before 22 months have gone by.

2) the rubber used on the knc heatsinks degrades to a point it is all covered in a fine oil. Much the same as if you sprayed the cube with WD-40 oil. Left the rubber mounts under
the board. That may not have been wise we will see.

3) after 22 months the thermal paste ...really really needs to be replaced. (clue: have to use a razor blade ..probably overdue)

4) It is a pain to clean with rubbing alcohol bit by bit but not too hard. The big deal imho is the 3000 rpm fan and the improved air flow with the knc kludge heat sink with
    rubber mounts gone. Looks like a wind tunnel. The fan is probably the biggest reason this works so well and cool now.

5) Huge upside on all this when done however with the dc/dc heat being much much less

below are my temps before and after in an 82F basement.

Typical Temp before 82F basement.



Typical temps after complete repaste with parts above listing in mind.



Quite the temp drop. Pretty dramatic. This was again in an 82F basement with the miners running.

End result when done below



So anyway the above parts and Maxumark X brackets really open the cube up to be much cooler as you can see from the above. Then again it may have mostly been due to
the dirt now gone. I'm just saying these are my results. So should be fairly easy to just grab the list of parts above and start working on your own dirty cubes.

Anyway just thought folk would be amused on how far I let them go...quite the motivator to fix thou when you wake up to the fact crap is this badly gone and dirty as hell

Hope it helps

Here is my new platinum dual 2560w Server PSU hack for anyone interested using a KNC Jupiter case. Figured what the heck had to zip tie it all together anyway. Doing so
with the KNC Jupiter case luggable/portable kinda sorta it may be made sense.

thread I started on this hack below

https://bitcointalksearch.org/topic/m.15533861

Complete build pics of he process are below.

lostgonzo.imgur.com

sample pic below so you get the idea



Anyway 2x the power of a Corsair 1200i platinum PSU for the same price and platinum efficiency. Well it works great.

Anyway looking for a psu server hack and info check out the above links.

enjoy!

I performed a re-pasting and cleaning a few months back along with the mods for better fan and heat sinks on the DC/DC converters. 
I used CRC Mass Air Flow Sensor cleaner from the AutoParts store to clean the boards when I had them removed from the case.  Worked great to remove the greasy mess from the rubber stuff KNC has in there.  Then blew them dry with some low pressure air.

FPGA is not hot to the touch.  I do run a fan in front of the controller.  Have an exhaust fan on the closet and the mods with the 3000 RPM fans and individual heat sinks on the exposed DC/DCs as I trimmed the based plate. Temps run 60C to 80C depending on outside temps as I have the miners in a closet with vents in the floor and an exhaust fan.  GenTarkin's Firmware is also in play.

I have a used backup controller coming so I may send this one to you to tinker with and see what happened.

Thanks for the info.

you may want to go back and see my prev posts on re-pasting etc my stuff was plenty dirty.....heh ...I also put a piece of glass under (from picture frame) the
titan controller board...seems to help keep it cool imho.....rather then have it sit on metal/or wood workbench

my setup here

lostgonzo.imgur.com

or at least part of it.....have equiv of 4 titans now ..1 hosted...other parted out in other part of basement etc

That worked great.  I should've thought to try that.  Now to remove the other LCDs so nothing is attracting insects.

Searing's got it. Never seen anything like that, possible the fpga output on that line shorted. I'd use another port and not worry about the display. Say, is the FPGA hot to the touch? If so it's on the way out, put a fan to keep it cool and when it goes send it over for fixing.

yank out the LCD and use this port instead is the quick fix ..if I understand the above correctly?

Hi.  I have a KNC Titan controller that has a bad ASIC Port 2 where the first data ribbon to a cube plugs. It was working fine for over a year but today I noticed hash had dropped and that the connected cube wasn't mining.
Culprit was a moth attracted to the LCD display I found on the bottom board by Port 2.
Inspected board but don't see anything amiss.
Swapped data cables between two connected cubes and issue stays with Port 2.  It did not follow the cube.

Thoughts.  Can this be repaired.

Just a note

I'd get from Maxumark (10 bucks i think they are) the X bracket replacement for the knc kludge heat sink with the 4 point screw downs
seems to balance better for more even setup imho.

Also we have not had any luck with the artic sliver...indeed got a guy's cube that did a mod like yours with the arctic silver and
it could only do 300mh and was quite ugly when i repasted it ..and it was supposedly done jan 2016

i used this stuff...it is a bit thick to put on...bu man it seems to do the trick

http://www.ebay.com/itm/181852749369?_trksid=p2060353.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

that is the best price...the artic silver from what I've seen is just too thin...this stuff is the best imho above link

anyway...just a thought on how this seems to work better imho

my temps are 50c / 60c as a result 84F in basement

my highest cube of all dies on 10 cubes is 71F

so anyway .....the bracket is slimmer...then the cut mod...also the large spiky copper heatsinks seem to work better also with the fan

but it is MOSTLY the fan for the improvements imho

anyway this is our results (maxumark has like lots and lots of titans) and myself (4 titans)

anyway just my 2c in that i just pulled apart an arctic thermal paste cube and was not impressed...was hottest cube
and also now can do 325 adv page settings at 41 amps and 64c highest die temp whole cube temp is 43.5c

where as when I got it in Feb...he said most it could ever do was 300mh...now doing 325 cool as heck and again basement at 84F...

so after my complete repaste and clean of all my 10 cubes with these mods...I went from like 700.5mh to 745mh ..so man what a diff

most of the diff was the cleaning (quite quite dirty) and the fans move a heck of a lot more air

here again is the parts list i use

https://bitcointalksearch.org/topic/m.15286157



for what it is worth

later