Newbie Rig (Help)

[shokatoo]

Here are my specs:
Gigabyte Z87X-OC with Intel® PentiumTM G3220 and Kingston 8GB 1600MHz DDR3 Non-ECC CL9 DIMM (2x4) as a base.
As hashing units I am expecting 4 MSI AMD Radeon HD 7950, 3072MB, GDDR5, 384bit to be delivered as we speak.
All this will be powered by one Sirtec - High Power PLUS GOLD 1200W - arrives on Monday... I hope.

I actually opted for this MB because I have no way to easily procure riser cables... from China they will arrive somewhere from 9 all the way to 29 of Januarry  

Have phun  

Can you please make some picture of Your rig?
I like this MB, and probably i will use it too without risers in this case.

Sure thing... but it has suffered a bit of modification as the video card supplier just run out of those... I've just bought 2 pieces of R9 280X... should be here tomorrow or the day after the most... I'll buy another 2 as they come up... somewhere

At the moment only the PSU has arrived... some 4 hours ago

[pontiacg5]

Uh oh!

A 280x has a TDP 50W greater than a 7950! Three on one 750W psu is not going to work, even if it is a real and true 750W PSU. 250x3=750W! I have many 280x's and when running best (near 710-750kh's) they bounce around 250-275W.

You may just swap one 750W PSU for a 850-1000W'er. You should be OK with two on a 750W supply + a PC, I have two 280x set up that way on a corsair 760i (built in load meter) and I see a load of around 700W/760@wall

This is a pretty bad 3930k machine with lots of extra stuff going on. You likely won't be pulling a full 700W

[Gwindor]

can u run three cards without risers in this mother board?

1x to 16x riser will arrive my country about 20 days.

and i think my motherboard has two x16 3.0 and one x16 2.0

if i use three of cards without risers it may give a problem?

i thought i can start with 3 cards so i can earn some coins till risers arrive here lol..

it is forbidden that putting 3.0 card to 2.0 slot?

[pontiacg5]

No, pci-e is backwards compatible. You won't hurt a 3.0 card putting it in a 2.0 slot.

You can run three cards on a motherboard, probably, but I don't think you would want to mine with it. Two won't have any room for cooling, so they will get exceptionally hot. It takes exceptionally loud external fans to cool 3 GPUs stacked on each other like that.

I would instead run two, so that the top card has some room to breathe.

[Gwindor]

No, pci-e is backwards compatible. You won't hurt a 3.0 card putting it in a 2.0 slot.

You can run three cards on a motherboard, probably, but I don't think you would want to mine with it. Two won't have any room for cooling, so they will get exceptionally hot. It takes exceptionally loud external fans to cool 3 GPUs stacked on each other like that.

I would instead run two, so that the top card has some room to breathe.

i got it thanks.

actually i will setup rig to an empty room that really a cold room. its winter here and the room is really cold.

by the way, about cooling issue three cards will be okey in this condition?

or still u dont advice run three of them without risers?

[pontiacg5]

Try it and see. I suggest keeping them below 90c at the very most, that might be hard even in a very cold room. I shoot for 75C on my miners, which can be hard to do.

For a short time (1-2 weeks) it may be OK, the cards are rated to 95c. The fans do not do well at temperatures like that, and will be the first thing to fail. Unfortunately, you'll just have to make a call. Is it worth the extra wear and tear on 2 cards for an extra 700kh/s for two weeks?

The cards should be OK running in a really cold room. I would try and stay above freezing, though. If it is a small room it will not take much time at all for it to be really, really hot! Prepare to be amazed!

[Gwindor]

Try it and see. I suggest keeping them below 90c at the very most, that might be hard even in a very cold room. I shoot for 75C on my miners, which can be hard to do.

For a short time (1-2 weeks) it may be OK, the cards are rated to 95c. The fans do not do well at temperatures like that, and will be the first thing to fail. Unfortunately, you'll just have to make a call. Is it worth the extra wear and tear on 2 cards for an extra 700kh/s for two weeks?

The cards should be OK running in a really cold room. I would try and stay above freezing, though. If it is a small room it will not take much time at all for it to be really, really hot! Prepare to be amazed!

yes i totally got u. really thank you. i m not ok in english and im also newbie about mining. that advices will prevent me from bad things.

i will run with two x16 3.0slot at first.

i also got two of 5970 cards but i will keep them for my future second rig or i will buy 1500w psu and run with 7 gpu but im not sure it will be safe or not.

5 gpus per rig, seems more safety for working.

[pontiacg5]

Try it and see. I suggest keeping them below 90c at the very most, that might be hard even in a very cold room. I shoot for 75C on my miners, which can be hard to do.

For a short time (1-2 weeks) it may be OK, the cards are rated to 95c. The fans do not do well at temperatures like that, and will be the first thing to fail. Unfortunately, you'll just have to make a call. Is it worth the extra wear and tear on 2 cards for an extra 700kh/s for two weeks?

The cards should be OK running in a really cold room. I would try and stay above freezing, though. If it is a small room it will not take much time at all for it to be really, really hot! Prepare to be amazed!

yes i totally got u. really thank you. i m not ok in english and im also newbie about mining. that advices will prevent me from bad things.

i will run with two x16 3.0slot at first.

i also got two of 5970 cards but i will keep them for my future second rig or i will buy 1500w psu and run with 7 gpu but im not sure it will be safe or not.

5 gpus per rig, seems more safety for working.

No problem, glad to help. Your English is pretty good actually.

Well, the thing to watch for is the input power. Here in USA line voltage is 110V, and a home circuit rated for 15A. Therefore, if you want any more than ~1500W input power you have to worry about home wiring being too small. This limits most US setups to 4 or 5 cards, especially 250W cards like these.

If your home circuits are 220V at 10A you have much more capacity than us Americans @  2200W. You could then theoretically run more than 1500W on one circuit (Please check this yourself, I don't know your area!) Maybe one 1500W PSU and one additional cheap one, for 7 cards one one circuit breaker.

I have never tried, but I have hear mixing GPU series (59xx+79xx/280x) on one computer can be hard sometimes. I can't help here, sorry!