Quote from: CYPER on January 10, 2014, 01:46:30 AM

Quote from: vesperwillow on January 09, 2014, 10:24:09 PM

Quote from: CYPER on January 09, 2014, 09:54:04 PM

What GPU pulls 350W?

I run 7970/280X decently overclocked. They each pull 340-360 on a good day. More if you want to really squash your balls on the wall, I've had them pull 380 before.

Quote from: CYPER on January 09, 2014, 09:36:09 PM

KNC board uses 3x 12V circuits to carry up to 15A of current.

A GPU uses 6x 12V circuits to carry up to 23A of current.

Which one looks more to you?

Yes, I understand 3x5a=15a and 6x3.8a=23a.

Quote from: CYPER on January 09, 2014, 09:36:09 PM

Are you aware that the PCI-E slot provides 75W of the total power?
Are you using powered PCI-E risers?

When you answer these questions you will understand that each 12V circuit on the GPU cabling uses less that the KNC board Wink

Yeah I'm aware of PCB design, and how the PCIx platform provides power. No, I don't use powered risers, all of the juice flows through the PCIE connectors, which means they flow more current than a normal setup.

You also should follow the conversation, specifically my ignored my question regarding pushing the KNC clock beyond stock to cause the wires to reach danger levels. Most 18AWG has a 4x-6x safety rating built in (depending on purity, oxygen content and sleeving)--even at 10amps they should be safe bundled together. Bundled @ 5amps (KNC design) they shouldn't be a danger.

KNC isn't loopy, which is why they knew they could use 18AWG for the boards.

This is why I proposed some airflow across them for anyone concerned about temps, and that they shouldn't be reaching such high temps anyhow unless something is wrong. Again, mine don't get near that, another reason I was asking about overclock.

Edit: My modules are running 145-155gh, the cable temps are 36.9C, the room is 26.7C. I have no form of cooling on the cables.

The bottom line is no GPU card can pull as much current per cable as a KNC board does.

Quote from: seanrarey on January 09, 2014, 11:20:58 PM

I run banks of 7970 GPUs pulling up to 450w _EACH_... yeah, it adds up.

I highly doubt that. I have a 7970 myself, so can speak from experience. I've ran benchmarks @ 1340Mhz / 7600Mhz and 1.33V core which is a lot.

Wow.

Mr Cypher, any experienced GPU miner will tell you that a tacked 7970 will pull more then 400watts. I tend to a substantial GPU farm on an hourly basis (it now mines LTC).

... so you are simply wrong. move on.

seanrarey

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