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Hello im newbie miner.

this will be my first rig.

im listing my bought list.

motherboard:     MSI Z77A-G45 Intel Z77 1155
gpu: 5x 7950 Powercolor  AX7950 3GBD5-2DHPP
cpu: INTEL CELERON G1610 2.6GHZ LGA1155 IVY BRIDGE
ram: HI-LEVEL 4GB 1600 MHz DDR3 RAM
psu:2x 750W


extra

1 ups for block high voltage

I am stucked about riser cables. which riser cables should i buy for running 5 gpu at once? 750wx2 is enough for power?

im planning mine some altcoins and i am worry about if i may do something mistake about building rig... thanks for help.

As a riser cable you should use 1x to 16x PCIe extenders/risers... as I understand they should work for all slots on your MB. But if you have the possibility you should buy the extenders for your specific ports. In your case 3 pcs. of 16x to 16x and the rest 1x to 16x (2 pcs. in your case).

I'm also building one  ;D
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  ;)

should i buy power included riser cables or not?

someone say if i use nonpower in risers may be cause of burned mb.

i bought this

http://www.ebay.com/itm/181281724794

16x to 1x.

Are u sure to be able to build a PC yourself?

yes i built myself pc but it is simple no need to care about thigs.

but about mining pc i will use 5 gpu and everything should be smooth. if i do something bad, gpus or mother board may get burned.

so i should buy things that will run smooth on my rig.

and sorry for my bad english.

start with getting ONE card working, then start adding more cards

you might be pushing it with a 750 watt psu for 5 cards

thanks. simple but good tip.

im curious about how will i know how much watt /s using my rig to calculate electric fees?

here you can calculate profitability and costs http://www.coinwarz.com/cryptocurrency

Can you please make some picture (http://imageshack.us/) of Your rig?
I like this MB, and probably i will use it too without risers in this case (https://bitcointalk.org/index.php?topic=361613.0).

i mean how will i see how much my rig is using electric?

i see some stuffs around on youtube videos and some rig pictures but i cant get what they actually using.

Normally, to find power supply size you add TDP of all components and add 20%. Google "TDP 7950" will get you the answer.

Anyway, it is 200W. You need 1000W for 5 GPU alone then, plus another 100-150W for the motherboard and processor. If you overclock you should plan for 225-250W per card even.

So, you need at least a 1100W power supply, but you should buy a 1200-1300W one for better results. Cheap ones are over-rated. Combining them is OK, but be mindful that you load them evenly.

i am sorry my english is not good and i cant know the keywords about something weird for me. like TDP 7950, for example i dont know what is tdp.

thanks for help. i already bought 2 of 750w psu and i think this will be enough. three cards to one psu and two cards + rest systrem to an other psu.

i will try to run with windows 8 and yes i will try to make some overclock and i will try to reduce volt. i think mis after burner will be okey for overclock and undervolt?

thanks.

You seem to have done your homework. TDP means Thermal Design Power, and it roughly translates to power draw/cooling capacity at full load. Things like overclock, or even running extra hot, will make the card run over TDP. CPUs also have a TDP, though it is not relevant for mining.

Splitting the PSU load that way should be OK. With 7950 you might be able to use windows 7, though windows 8 or linux will be a better bet. You can't undervolt with afterburner in linux, but sometimes there are other ways to lower voltage and overclock. I have 6 MSI 7950's that CGminer easily overclocks/undervolts in linux right out of the box, sometimes you get lucky  ;D

I do have a question reagarding the riser cables though..

Most either use the 16x extenders or the 1x-16x riser. Even recommendations on alot of sites for mining rig builds mention the 1x-16x. My question do 8x-16x risers have a problem? as there are almost no posts about them.

Why would you? A riser cable adds latency, and they are rather crummy for gaming. 8x is a total waste for mining, and just makes the riser cables more likely to break, harder to route, and they will interfere with airflow more.

Don't waste money, just get 1x-16x cables.

mostly cos 8x-16x are more easily available where i am.. as in i cant find any 1x16x risers and 16x extenders

also my mobo follows this design

From top to bottom so i can get 2 double wide cards but can kiss the 1x good bye..

-16
-1
-16
-1
-8
-8

Not if you put the x16 cards on x1 riser cables too. You are going to want to do that anyway, because the card in the top slot will be melted to pieces by the time the card in the 2nd x16 slot is done with it. Also, your mobo has x8 slots? Must not be consumer level hardware?

Yeah, 8x cables will work but there's probably a reason there all you can find. The 1x cables are all sold out! If you wanted you could either trim the x8 ribbon cable down to x1 so it fits in the 1x slots, or you can cut out the back half of the 1x pcie connector, so the 8x card hangs long.

From this
http://img.auctiva.com/imgdata/0/4/2/7/2/6/webimg/211070749_o.jpg


To this
http://blog.zorinaq.com/images/tiptocutpciex1.jpg

wow i dint think i could do that..

If it's what you've got on hand and you've got the steady hand sometimes mgyver style is the way to go  ;D

It is why I prefer x1 risers though, they'll always work, in any motherboard.

Here's a pic of x1 in x16, works a champ.

http://i879.photobucket.com/albums/ab357/pontiacg5_2010/DSC_0164_zps05b56ec2.jpg

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 :)

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

http://i879.photobucket.com/albums/ab357/pontiacg5_2010/mining_zps282f6a64.png

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?

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?

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!