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Topic: Mining farm parts (Read 1187 times)

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Play2Live presale starts on 25th January
March 25, 2014, 05:06:06 AM
#7
Yes perfect answer very detailed and i understand everything. I think i am stuck now as order of PSU has been filled on website by friend yesterday already not sure if i can cancel it now.
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Activity: 192
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March 24, 2014, 10:44:06 PM
#6
Somewhere in the middle of the development of the ATX power supply specification somebody thought there was a maximum power per rail restriction before you created the potential for a fire.  And, as a result, consumer power supplies started having more than one "rail".  Each rail has a maximum total power below that magical limit.  A 1000 watt supply would have 4 "rails".

Now this in itself isn't any big deal as long as you know which plug is on which rail.  In the beginning it was easy.  A dual rail supply had one rail dedicated to the CPU and one rail serving everything else.  Easy.  The 4 pin plug going to the CPU had half the capacity.

But then we started getting high power GPU's, and people using high power GPU's with low power CPU's.  Mining is a great example.  Miners don't want to reserve / allocate / waste 250 watts of their 1000 watt supply for the CPU, especially since they are going to put a low power processor in there.  But, with a traditional multi-rail supply you are stuck.  That is unless you do some fancy connector jiggermary.

A 4 rail supply like linked by the OP is likely (and I am guessing here) to have 1 rail dedicated to the CPU, 1 for everything but PCIe and two split across the PCIe power plugs.   Yes, that's right.  You bought a 1000 watt supply for your GPU's but half of it is unusable by the GPU's.  Ok, I exaggerate.  You can recover some of that power from one of the rails through the PCI backplane and a bit more from the molex connectors.

Personally, the safety of a multi-rail supply has been debunked.  It is no longer a requirement of the ATX power supply specification.  I for one see no reason to buy a multi-rail supply.  It just makes you think more about what you want to do and occasionally stand on your hands and touch your toe to your ear to get the supply to run all your gear.  I don't need those contortions.  Thus I recommend single rail supplies.  You can be smart or you can be lazy.  I choose to be lazy Wink

If you are the average joe consumer who is building himself a hot rod computer with a decent processor and a decent video card and a bunch of peripherals then a multi rail supply will work just fine.  Your i7 will be perfectly happy on one of the rails, your video card will be perfectly happy on another and one to run the rest.  No problems at all.

But, if you are trying to run three video cards, all of which want 300 watts each, then using a multi rail supply that dedicates 250 watts to the CPU leaves you 750 to run 900 watts worth of GPU.  You can get a maximum of 150 of that 900 from the pci backplane leaving you needing 750 watts from the PCIe power plugs which are spread across 500 watts worth of capacity.  Not a good situation to be in.

Now, realize that this is purely speculative about what the supply manufacturer did and purely theoretical.  You may, and many do, get away with ignoring the specified individual rail limits.  But I only buy single rail supplies.

Does that help?
full member
Activity: 179
Merit: 100
Play2Live presale starts on 25th January
March 24, 2014, 02:42:50 PM
#5
Ok thanks guys, fractalbc could you explain a bit more with what is wrong with PSU connectors? I dont want to have something too difficult to setup as i have not done setup of farm before, maybe i should rather pick some other PSU then.
sr. member
Activity: 434
Merit: 251
March 24, 2014, 02:09:31 PM
#4
i can sell you a gigabyte 280x oc battlefield edition with game key
https://bitcointalksearch.org/topic/wts-gigabyte-r280x-oc-gigabyte-7950-523644
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Activity: 192
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March 24, 2014, 12:37:46 PM
#3
That reviewer does everything in their power to hide the specs but careful use of the magnifier on the pictures confirm ... it is a multi rail supply.

Not that you can't use a 4 rail supply.  You just need to know which plug is on which rail to balance the load or at least not overload any one of the 4 rails.

So, unless that is the only supply on the planet available to you, you can do better.

Video card brand names are as much voodo cult legend as anything.  Gigabyte is fine.  I won't touch asus with a 10 ft pole.  I used to buy them many years ago but the proprietary fan control scheme drove me away.  Things may have changed since then.
sr. member
Activity: 406
Merit: 250
March 24, 2014, 12:03:37 PM
#2
Gigabye is OK, nothing special, a friend of mine has them. He is much more satisfied with Asus. Regarding PSU, never hear of that company and I think it might not be sufficient unless heavily undervolted.
full member
Activity: 179
Merit: 100
Play2Live presale starts on 25th January
March 24, 2014, 08:53:16 AM
#1
Hey guys i am just  checking if anyone has first hand information on quallity of Gigabyte R9 280x Windforce 3x OC cards for mining, and BeQuiet 1200W PSU
http://www.kitguru.net/components/power-supplies/zardon/bequiet-dark-power-pro-10-1200w-psu-review/

Could i bare 4 cards on such PSU, or is 3 max, and also is this company BeQuiet good standart becouse i havent yet heard much about it.
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