Hacking The KNC Firmware: Overclocking

[tzortz]

I am sorry but cannot understand the usage of your plates.

Can you please explain a little more?

[crashoveride54902]

This is probably off topic so please forgive me. My KNC Jupiter case is all scratched up and looks like hell. I was wondering if anyone has powder coated their case? I called up a company and got a quote for $60 to do a flat black exterior power coat. I would remove all fans and modules and give them the case. What do people here think about the idea? Please don't hate on me  

i don't think anyone has done that...but why would you still be using the case? you get so much better temps outside the case

[Ski72]

I am sorry but cannot understand the usage of your plates.

Can you please explain a little more?

the plate/bar is not as large as the one currently installed on the Neptune, nor will the foam be intruding on airflow over the VRMs.  It is the same design as was used to hold the radiators and ASICs together on the Jupiter.

This how the Arctics were mounted to the ASICs on the Jupiter ...



and using only the two holes, front and back, the end result opens the board (VRMs) for better air flow ...



off to sleep ... hopefully tomorrow is a better day for "receiving" 

[Elenelen]

No, sorry Ski72....

You need something like this:

[crashoveride54902]

No, sorry Ski72....

You need something like this:

wonder if that is the same size as a cpu cooler mounting bracket?

[Ski72]

No, sorry Ski72....

You need something like this:

That's how they are mounting it now, yes, with the airflow in that direction. 
The way it is/was mounted on the 28nm board, is with the radiator turned 90^o clockwise, and the front/face of the radiator in the direction of the PCIE and ten pin connectors.

Basically you'd take the board out of the box, mount the radiator as above, and put a fan on the radiator. You're still getting the same airflow across the radiator for cooling purposes, and take away all the foam, more airflow around the VRMs.  Also, looking at the other pics from crash and tzortz, you could then put little heat sinks on the VRMs.

Just a few thoughts ...

[Ski72]

No, sorry Ski72....

You need something like this:

wonder if that is the same size as a cpu cooler mounting bracket?

Yes. I import it (the pic) into AutoCAD and the board is the same size as the Jup boards (I compared them side by side, dimension wise, in AutoCAD), and the holes are in the same places, just a different layout of the VRMs.

[fubly]

Powering up the chip! Thats KNC's problem.



Hashfast squeez out 500 Gh/s on this design, with 28nm. For this must it be possible to squeez out 1,5 Th/s per 20nm chip.

KNC have to redesign the board and the controller.

[Elenelen]

I have removed the Neptune aluminum plate. Now I can see the Ericsson VRM's..... this is bad: they are the BMR4641002 (max 40A) instead of the BMR4641008 (max 50A).    ...... no OC possible !

The 1002 has a OverCurrentProtection of 48A and looking to my Advanced-page: nearly all the VRMs are already around 46-47A (and this is KnC's default setting).
They should have used the 1008 instead, which has 50A and an OCP of 62A.

[rograz]

Hashfast squeez out 500 Gh/s on this design, with 28nm. For this must it be possible to squeez out 1,5 Th/s per 20nm chip.

KNC have to redesign the board and the controller.

There are other metrics than process node that determines final performance, as a matter of fact process node mostly impacts efficiency and density and the only real effect on "performance" it has is allowing higher operational frequency. A transistor does not perform better just cause it's smaller than it's predecessor, yes you can pack more of them in the same area but performance/transistor at the same frequency stays the same from one node to the other.

[AFox]

Is it possible to peal of the yellow sticker from the VRMs ?
Is it safe the put aluminum or cooper heatsinks directly on the VRMs with only thermal paste (link) and not thermal adhesive pads (link) ? As VRMs convert electricity and heatsinks are electrical conductors.

[Elenelen]

Is it possible to peal of the yellow sticker from the VRMs ?
Is it safe the put aluminum or cooper heatsinks directly on the VRMs with only thermal paste (link) and not thermal adhesive pads (link) ? As VRMs convert electricity and heatsinks are electrical conductors.

Yes. I pealed the yellow sticker from the VRM, and put the heatsink on top.  See pictures in next posts....

[Elenelen]

OK, here is my DIY cooling-project:








more pictures will follow

[Elenelen]

Here some more:

[Elenelen]

And this is the result: 20 degrees lower on the VRM's :

[crashoveride54902]

nice work elenelen looks good

[butjust41day]

And this is the result: 20 degrees lower on the VRM's :

Considering some of your VRMs were over 100 degrees (based on pictures you posted earlier). I think you could safely say you achieved as high as 30 degree reduction on some VRMs. I think the VRMs and the fact that they are they are the BMR4641002 (max 40A) instead of the BMR4641008 (max 50A) as you mentioned earlier are the most disappointing aspect of the current design (KNC that's not a criticism; but a critique). I do understand that KNCminer was under a lot of pressure to ship before the end of the month. I wonder if they were expecting far greater power savings and that is why the board does not have the 1008s.

I think delivery dates written in stone are a two edged sword. They give targets to be achieved; but, can result in shipping before every important detail is fully dealt with. Hopefully we'll see revised boards coming.

[Elenelen]

Considering some of your VRMs were over 100 degrees (based on pictures you posted earlier). I think you could safely say you achieved as high as 30 degree reduction on some VRMs. I think the VRMs and the fact that they are they are the BMR4641002 (max 40A) instead of the BMR4641008 (max 50A) as you mentioned earlier are the most disappointing aspect of the current design (KNC that's not a criticism; but a critique). I do understand that KNCminer was under a lot of pressure to ship before the end of the month. I wonder if they were expecting far greater power savings and that is why the board does not have the 1008s.

I think delivery dates written in stone are a two edged sword. They give targets to be achieved; but, can result in shipping before every important detail is fully dealt with. Hopefully we'll see revised boards coming.

I agree: KnC should have used more robust VRM's.

And indeed I had 107 degrees with some of the slot-1 VRM's due to a gap between pad and VRM... see this picture:

[butjust41day]

Considering some of your VRMs were over 100 degrees (based on pictures you posted earlier). I think you could safely say you achieved as high as 30 degree reduction on some VRMs. I think the VRMs and the fact that they are they are the BMR4641002 (max 40A) instead of the BMR4641008 (max 50A) as you mentioned earlier are the most disappointing aspect of the current design (KNC that's not a criticism; but a critique). I do understand that KNCminer was under a lot of pressure to ship before the end of the month. I wonder if they were expecting far greater power savings and that is why the board does not have the 1008s.

I think delivery dates written in stone are a two edged sword. They give targets to be achieved; but, can result in shipping before every important detail is fully dealt with. Hopefully we'll see revised boards coming.

I agree: KnC should have used more robust VRM's.

And indeed I had 107 degrees with some of the slot-1 VRM's due to a gap between pad and VRM... see this picture:

The edges of the aluminium indicate they use a mechanical shear to cut the plate. At least if memory serves me right it's been over 30 years since I used a shear. It's brute force and tends to twist the aluminium plate.

[greghawk]

Is it possible to peal of the yellow sticker from the VRMs ?
Is it safe the put aluminum or cooper heatsinks directly on the VRMs with only thermal paste (link) and not thermal adhesive pads (link) ? As VRMs convert electricity and heatsinks are electrical conductors.

Yes. I pealed the yellow sticker from the VRM, and put the heatsink on top.  See pictures in next posts....

is it even necessary to peal the yellow stickers off?