Taming the C6100

Mrlie

Member
Jan 1, 2011
32
2
8
44
Oslo, Norway
No. There is no way for the FCB to recognize what fans are connected. If the fans you installed are not spinning up, it is more likely what PigLover said:
If the fans did not spin then odds-on the pinout for the adapter cable you used is wrong.
My mind was busy, so unfortunally I didnt pay enough attention to everything what PigLover said, but now I see you're both right.
Took a closer look at the order of the cables in the adapter-cable, and sure enough the order is different from the connector to the fan, than the connector to the FCB. It can also be clearly seen in the photo on the eBay-auction I linked to. At first I only looked at the connector to the fan, and it matches 100% to the order on the fan it self. I think I just assumed that it would be the same on the other end.

I guess I need to find some new cables, or find the parts to make my own. Thank you both very much :)
 

carlding

New Member
May 14, 2013
16
0
0
I got one C6100 from the same seller. The fans are the delta 3.3A ones. Rated at 65 dB(A), they are apparently too loud for home use.

I have been searching for alternatives. PigLover and RimBlock and a few other forumers have shared various models. Here comes another possibility: AVC DATA0838B 2U, the specs of which are as follows:
air flow: 88.16 CFM
pressure: 20.4 mm H[SUB]2[/SUB]O
noise: 52 dB (I suppose this is the max noise level)
RPM: not found.

Any one tried this fan before? Will 52 dB still be too loud? any comments? Thanks.
 

Rain

Active Member
May 13, 2013
266
104
43
Any one tried this fan before? Will 52 dB still be too loud? any comments? Thanks.
I've never heard of that company/fan before.

Whether or not 52dB will be too loud for "home use" depends on where the server will be and what kind of load you will put on it. I have the Evercool fans that PigLover used in a c6100 that I use at home. My stretch-goal was to get it quiet enough to go into the rack next to my desk that houses a few Norco chassis (2x2U and 1x4U) with Noctua fans. At boot, the thing is dead silent, but once you put any sort of light load on it the fans bump to about ~3900RPM. At this speed, it is too loud to sit next to (or even across the room from). I'd say it is just loud enough to be annoying. It's definitely quiet enough go in a separate room though (which is what I plan on doing, when I find the time).

tl;dr: With any fans, it is unlikely you will make it quiet enough to sit next to. Any fans with similar spec to those mentioned in this thread should work in a separate room though.
 
Last edited:

carlding

New Member
May 14, 2013
16
0
0
I've never heard of that company/fan before.

Whether or not 52dB will be too loud for "home use" depends on where the server will be and what kind of load you will put on it. I have the Evercool fans that PigLover used in a c6100 that I use at home. My stretch-goal was to get it quiet enough to go into the rack next to my desk that houses a few Norco chassis (2x2U and 1x4U) with Noctua fans. At boot, the thing is dead silent, but once you put any sort of light load on it the fans bump to about ~3900RPM. At this speed, it is too loud to sit next to (or even across the room from). I'd say it is just loud enough to be annoying. It's definitely quiet enough go in a separate room though (which is what I plan on doing, when I find the time).

tl;dr: With any fans, it is unlikely you will make it quiet enough to sit next to. Any fans with similar spec to those mentioned in this thread should work in a separate room though.
Plan to put it in an enclosed balcony. When switched on, the fans stay at 6000 RPM with no load. I got the noise level measurement 1 meter away from the server using an mobile phone application, and it's about 75 to 80 dB. Right now, I am thinking of either swapping the fans or modifying the PWM duty cycle to reduce the fan speed. Not sure whether a 555 timer will help the latter.
 

Dr_Drache

New Member
Jun 7, 2013
26
0
1
Plan to put it in an enclosed balcony. When switched on, the fans stay at 6000 RPM with no load. I got the noise level measurement 1 meter away from the server using an mobile phone application, and it's about 75 to 80 dB. Right now, I am thinking of either swapping the fans or modifying the PWM duty cycle to reduce the fan speed. Not sure whether a 555 timer will help the latter.
swap fans to the Supermicro FAN-0074L4, IMO the best move you can make.

modding the PWM duty cycle in this case will not work, because the FCB uses the RPM to adjust the PWM, so unless you mod both forward and return signals, the FCB will fight your mods,
HONESTLY i'd like someone to mod the FCB bios (both PIC18 and PIC16) to allow custom fan curves to be programmed in, that would be the best
 

Patrick

Administrator
Staff member
Dec 21, 2010
12,382
5,534
113
swap fans to the Supermicro FAN-0074L4, IMO the best move you can make.

modding the PWM duty cycle in this case will not work, because the FCB uses the RPM to adjust the PWM, so unless you mod both forward and return signals, the FCB will fight your mods,
HONESTLY i'd like someone to mod the FCB bios (both PIC18 and PIC16) to allow custom fan curves to be programmed in, that would be the best
That would be very cool!

Did you get the Supermicro fans in no problem?
 

Dr_Drache

New Member
Jun 7, 2013
26
0
1
That would be very cool!

Did you get the Supermicro fans in no problem?
no problem at all, just dremled the sides, and connected wires..... completely different system, i'll look into the firmware, no promises, I have alot on my plate

What do I need to check, if anything, to verify those supermicro fans will work?
you have a C6100? Yes? they will work :p
 

carlding

New Member
May 14, 2013
16
0
0
swap fans to the Supermicro FAN-0074L4, IMO the best move you can make.

modding the PWM duty cycle in this case will not work, because the FCB uses the RPM to adjust the PWM, so unless you mod both forward and return signals, the FCB will fight your mods,
HONESTLY i'd like someone to mod the FCB bios (both PIC18 and PIC16) to allow custom fan curves to be programmed in, that would be the best
I'm just worrying about the supermicro fans not giving enough CFM (68.3) and air pressure (0.53 inch H20). The CPUs may be overheated if all 4 nodes are under heavy load.

The max duty cycle that a PWM chip can produce is 100%. If we can intercept the pulse and reduce the duty cycle by half and then send the new signal, the max duty cycle that can be received by a fan is 50% (corresponding to around 4000+ RPM of the default Delta fans). It could be better if the sense line can be modified as well.

For the FCB firmware mod, is there any reference? Thank you.
 

RimBlock

Active Member
Sep 18, 2011
838
28
28
Singapore
My Supermicro fans are still chugging allong quite happily. My nodes are not under very heavy loads though (ESXi node with Win Serv 2012 Ess, A Solaris SAN & a CentOS Minecraft server). On the other hand the server is in a rack in a room with an ambient temp of around 34Deg C and I have had no issues.

I finally put my unmodified uinits for my Hadoop build in my rack this weekend and the noise is significant from them. With the sides on and the front closed (back open) the modified unit is a light hum.

RB
 

Dr_Drache

New Member
Jun 7, 2013
26
0
1
I'm just worrying about the supermicro fans not giving enough CFM (68.3) and air pressure (0.53 inch H20). The CPUs may be overheated if all 4 nodes are under heavy load.

The max duty cycle that a PWM chip can produce is 100%. If we can intercept the pulse and reduce the duty cycle by half and then send the new signal, the max duty cycle that can be received by a fan is 50% (corresponding to around 4000+ RPM of the default Delta fans). It could be better if the sense line can be modified as well.

For the FCB firmware mod, is there any reference? Thank you.
I have zero reference currently, other than i know it's been done on nearly every consumer device with a following (videocards for example) I havn't had time and won't for a bit, to look into it.
my idea is not to "slow" the fans as much, but make the curve more linear, with a higher min speed, and max speed at a cooler temp, as weird as it sounds, on videocards it keeps the system cooler
with less noise (less spikes) - I'd also be willing to look into a 120MM fan mod (would require only usage of 2 HDD trays though) I'm still waiting on proper parts for my cables, let me know if this is a mod
people would be intrested in me undertaking, i THINK i have something that would work.
on the deltas @ 50%, that's 50% CFM but not 50% noise (the DBa isn't linear, but the flow is), and at 100% then the supermicros are not much louder, and are flowing better, and I've personally only ever worried about
static pressure for things IMO that need it, such as radiators or items that are flow restricted, we are not QUITE there, so as the static pressure helps, I don't think it should be a TOP stat above CFM in this.
 

carlding

New Member
May 14, 2013
16
0
0
My Supermicro fans are still chugging allong quite happily. My nodes are not under very heavy loads though (ESXi node with Win Serv 2012 Ess, A Solaris SAN & a CentOS Minecraft server). On the other hand the server is in a rack in a room with an ambient temp of around 34Deg C and I have had no issues.
Hi RimBlock, good to hear that. I expect my nodes to be under heavy load with some number crunching work. That's why I am looking for some alternatives.
 

carlding

New Member
May 14, 2013
16
0
0
my idea is not to "slow" the fans as much, but make the curve more linear, with a higher min speed, and max speed at a cooler temp, as weird as it sounds, on videocards it keeps the system cooler
with less noise (less spikes) -
I used to do the same thing for my macbook pro. Anyway, I don't have a clue yet on how the firmware mod can be achieved unless we can find some documentation or source code.

I'd also be willing to look into a 120MM fan mod (would require only usage of 2 HDD trays though) I'm still waiting on proper parts for my cables, let me know if this is a mod
people would be intrested in me undertaking, i THINK i have something that would work.
I'm certainly interested :) but not sure how the 120MM fans can be fitted into the chassis using the HDD trays.


on the deltas @ 50%, that's 50% CFM but not 50% noise (the DBa isn't linear, but the flow is), and at 100% then the supermicros are not much louder, and are flowing better, and I've personally only ever worried about
static pressure for things IMO that need it, such as radiators or items that are flow restricted, we are not QUITE there, so as the static pressure helps, I don't think it should be a TOP stat above CFM in this.
In fact, 50% is just an example, it could be any percentage as long as the thermal dissipation requirement can be satisfied. Regarding to the nonlinearity, I hope the noise v.s. fan speed curve is sort of convex? I could be wrong though...
 

Dr_Drache

New Member
Jun 7, 2013
26
0
1
I used to do the same thing for my macbook pro. Anyway, I don't have a clue yet on how the firmware mod can be achieved unless we can find some documentation or source code.


I'm certainly interested :) but not sure how the 120MM fans can be fitted into the chassis using the HDD trays.



In fact, 50% is just an example, it could be any percentage as long as the thermal dissipation requirement can be satisfied. Regarding to the nonlinearity, I hope the noise v.s. fan speed curve is sort of convex? I could be wrong though...
the firmware mod will be like 90% of any other bios mods, flag discriptors in hex. it would HAVE to be binary editing, and the only refernce we'll get is the controller's chips datasheets.
 

RimBlock

Active Member
Sep 18, 2011
838
28
28
Singapore
I'm certainly interested :) but not sure how the 120MM fans can be fitted into the chassis using the HDD trays.
Quite an interesting idea certianly but with a 3.5" hard drives width being 101.6mm and the height being 25.4mm (on average) a 120mm fan is unlikely to fit in the chassis.

There is, however, scope to put 1 or more 120mm fans on the front of the chassis with a cowling that feeds the air in to the empty drive bays. Probably not the prettiest solution but it should work with a bit of engineering. You may end up blocking a U or two above and below the server though.

RB
 

Dr_Drache

New Member
Jun 7, 2013
26
0
1
Quite an interesting idea certianly but with a 3.5" hard drives width being 101.6mm and the height being 25.4mm (on average) a 120mm fan is unlikely to fit in the chassis.

There is, however, scope to put 1 or more 120mm fans on the front of the chassis with a cowling that feeds the air in to the empty drive bays. Probably not the prettiest solution but it should work with a bit of engineering. You may end up blocking a U or two above and below the server though.

RB
specualation is fun, but let me get a drawing made up, and some measurements done...
 

benso37

New Member
Jun 25, 2013
18
0
1
Help!!

I just took delivery of one of these monsters yesterday and upon starting all nodes, I realized that the amber/green lights keep flashing. Has anyone experienced this with their unit. All nodes go through post without any issues. I've contacted the ebay seller but any help on here will be greatly appreciated.

Thanks
 

benso37

New Member
Jun 25, 2013
18
0
1
One. I don't have redundant power supply and I don't think the one power supply can take multiple cables.
 
Last edited: