1300W PSU only 8 PCI cables but I need 10!

[dannygroove]

The question is about your PSU cables. The answer, then, is also about your PSU cables. If your PSU has PCIe cables made from 16AWG wire, it should be okay. If your PSU has PCIe cables made from 18AWG wire, I'd say it's a poorly-thought-out design.

How can I know the quality of the cables? This is the product http://holybitcoin.com/product/holy-bundle/

Thanks for your time, Its getting clearer to me

Keep in mind that power supply is 1300w at 240v and only 910 at 120v.

Thats true, thanks for the heads up

[QuintLeo]

Great, I also found out on the internet that a a 16AWG cable can handle up to 3.7 Amps
Source: http://www.answers.com/Q/How_much_current_can_a_16_gauge_wire_handle

 Dunno where they got that answer from, but it's WAY on the low side.

 16 AWG in most usage is good for at least 8 and possibly as high as 10 amps.

 The national electric code doesn't go that low, but if you take their rating for 14 AWG (a VERY VERY conservitive 15 amps) and pro-rata for the relative circular mil area of a 14AWG to a 16AWG you get a much more accurate while still conservative figure.

I've been turning away DPS2K sales all week on account of we're out of stock.

 BAD timing.
 8-O

[notlist3d]

Great, I also found out on the internet that a a 16AWG cable can handle up to 3.7 Amps
Source: http://www.answers.com/Q/How_much_current_can_a_16_gauge_wire_handle

 Dunno where they got that answer from, but it's WAY on the low side.

 16 AWG in most usage is good for at least 8 and possibly as high as 10 amps.

 The national electric code doesn't go that low, but if you take their rating for 14 AWG (a VERY VERY conservitive 15 amps) and pro-rata for the relative circular mil area of a 14AWG to a 16AWG you get a much more accurate while still conservative figure.

I think they were talking about 16 awg for a splitter.  For a 2 PCIe splitter to be exact.  So it's not going to get anywhere near 10 amps.

But I think your thinking of the electric cord running, and they are saying for a splitter.  So 2 different things.

[Finksy]

Here's a better figure of ampacity for stranded cabling in DC setting: http://www.westmarine.com/WestAdvisor/Marine-Wire-Size-And-Ampacity

More importantly however, the connectors used for PCIe (Molex mini-fit JR: http://www.molex.com/pdm_docs/ps/PS-5556-001.pdf) specify a maximum amperage of 8-9A per 16awg circuit in a 3-powered-circuit connector, depending on the type of pins used. Or, 288-324W maximum per connector.

They are also rated to a maximum of 105*C (including a maximum 30*C temperature rise over ambient for the connector).

Edit: To answer your question, Bitmain "requires" that all 3 PCIe sockets are used per hashing board.  Each hashing board on an S7 draws somewhere around 360-370W DC, so with proper 16awg cabling (Scott's is good quality 16awg), if you were to use a splitter for 2x of the PCIe sockets to feel better about it (and be 100% sure not to violate warranty terms), you would be well within the safe range for amperage of the wiring and connectors/pins.

[alh]

It's quite possible that this ongoing consternation of how many PCIe power connectors are needed relates to your interpretation of the PCIe specification for the power connector. I think the original spec only REQUIRED that two of the +12V lines be present. All three of the GND wires were required, but it was perfectly "legal" to only have two +12V lines. So if you interpret the PCIe spec very conservatively, 3 connectors would guarantee that there were 6 actual +12V pins.

Of course virtually no PSU vendor did that so, all three +12V pins carry current these days. So with two PCIe connectors on a current PSU, you get 6 conductors, which is the same as three "legal" PCIe connectors.

Since they don't want you to have more than one +12V rail for a blade, I think that's a pretty clear indication they are all joined in parallel on the board. In addition, things still work well, even if one of the pins has a marginal crimp, or just fits poorly, if all the connectors are used.