setup question on first rig build

[rolyasm]

Hi all. Great forum. I have my first build almost complete and just need a few pointers to finish. My question is about how to power the 4x7950's I am running. I have 4 x 1x16 power riser cables connected into PCIe 1-4, 2x16 and 2x1. First off, does that work or should I use the last x16 I have. I am assuming it doesn't matter. Now to power. The risers have a molex 4 pin connector on each riser. They also have 2 unused Crossfire connectors on each card. I have seen people use and not use the Crossfire and not sure how to determine when not to. So my questions, in a nutshell are this:
1) Are my risers in the correct slots
2)Do I connect the Molex power cables directly from the power supply, and if so, can I use one cable from the PSU that has dual connectors, so in essence running 2 cards from one cable?
3)What do I do with the Crossfire tabs on top?
Thanks everyone in advance.

[Nipperkin]

1) Are my risers in the correct slots

Yes, you should be fine running it like this.

2)Do I connect the Molex power cables directly from the power supply, and if so, can I use one cable from the PSU that has dual connectors, so in essence running 2 cards from one cable?

Correct, connect these, and having multiple molex connectors on the same cable is fine.

3)What do I do with the Crossfire tabs on top?

I personally haven't had any luck keeping these connected while mining...made the machine unstable and lower hashrate.  I think the consensus is to not connect these still.

[alose]

Crossfire in mining, dont use. It will actually slow it down.

As for the powered risors it should be ok to run 2x cards on one strand. This will not be the only thing powering the card. Its just to make up for the smaller amount of power that would normally come from the motherboard. Its the 8pin or 6pin connectors that you want to come from differnet strands.

Also:
1. you may need to make dummy plugs to mimic monitors
2. you may need to jumper wire the pcie 1x to get it to work. (I had to)

[rolyasm]

Thanks for the quick replies. I am almost ready light the rig up. I have read a little on the dummy plugs, hopefully I won't need them. I am sure I can find some pictures and posts on how to run a jumper wire if needed. Hopefully it will just work, but as my luck typically is, I am not expecting everything to run smoothly. Wish me luck.
Roly

[rolyasm]

Man, I feel so Newbie-ish, but here goes
To review, I am using 7950's, have powered risers and have each Molex connected and the pin connector/riser to the motherboard..
Is this enough power or do I need to hook up power to the VGA pins on the top of the card. Not sure that is what they are called, I will try to attach a pick. On the top of each card are 2 sets of VGA, 6-pin connectors. They have 2 square pins and the other 4 are kind of shaped like a house. Looking at pictures it looks like everyone has these connected. So my question, again is:
1)Do I need to also power the card with the 2 sets of VGA power pins or is the Molex and the riser enough. I have the cables to connect them, so it is easy to do. Thanks in advance for your reply.

Edit: Another problem: I only have 6 VGA outputs on my PowerUnit. Do I need to get splitter if I want to connect all 8, 2 on each card? Can I connect just one VGA on each card? I do have an extra Out on my Power, labeled CPU2. Can I use that as well. That way I would only be short one output on my power supply.

http://images.search.yahoo.com/images/view;_ylt=AwrTcYRI_MZSm6MAaMyJzbkF;_ylu=X3oDMTIzdDN0YTQ1BHNlYwNzcgRzbGsDaW1nBG9pZAMxMTBmZTJmMGUxYWZmNjg0ZTc5YzhkYWFlMTY1NzJkOARncG9zAzQwBGl0A2Jpbmc-?back=http%3A%2F%2Fimages.search.yahoo.com%2Fsearch%2Fimages%3Fp%3D7950%2Bvga%2Bpower%2Bpins%26fr%3Dmcafee%26fr2%3Dpiv-web%26tab%3Dorganic%26ri%3D40&w=800&h=600&imgurl=i48.tinypic.com%2Ffursi8.jpg&rurl=http%3A%2F%2Fwww.gamexeon.com%2Fforum%2Fhardware-article%2F93943-review-his-hd-7950-iceq-cocok-untuk-yang-suka-overclock.html&size=239.2KB&name=Konektifitas+yang+di+gunakan+oleh+%3Cb%3EVGA+%3C%2Fb%3Eini+cukup+lengkap+bahkan+agan+...&p=7950+vga+power+pins&oid=110fe2f0e1aff684e79c8daae16572d8&fr2=piv-web&fr=mcafee&tt=Konektifitas+yang+di+gunakan+oleh+%3Cb%3EVGA+%3C%2Fb%3Eini+cukup+lengkap+bahkan+agan+...&b=0&ni=96&no=40&ts=&tab=organic&sigr=13hh86gcl&sigb=13atthjbd&sigi=10q7fh2n2&.crumb=nACcx5MNzi/&fr=mcafee

[YourNerdyJoe]

Man, I feel so Newbie-ish, but here goes
To review, I am using 7950's, have powered risers and have each Molex connected and the pin connector/riser to the motherboard..
Is this enough power or do I need to hook up power to the VGA pins on the top of the card. Not sure that is what they are called, I will try to attach a pick. On the top of each card are 2 sets of VGA, 6-pin connectors. They have 2 square pins and the other 4 are kind of shaped like a house. Looking at pictures it looks like everyone has these connected. So my question, again is:
1)Do I need to also power the card with the 2 sets of VGA power pins or is the Molex and the riser enough. I have the cables to connect them, so it is easy to do. Thanks in advance for your reply.

Edit: Another problem: I only have 6 VGA outputs on my PowerUnit. Do I need to get splitter if I want to connect all 8, 2 on each card? Can I connect just one VGA on each card? I do have an extra Out on my Power, labeled CPU2. Can I use that as well. That way I would only be short one output on my power supply.

http://images.search.yahoo.com/images/view;_ylt=AwrTcYRI_MZSm6MAaMyJzbkF;_ylu=X3oDMTIzdDN0YTQ1BHNlYwNzcgRzbGsDaW1nBG9pZAMxMTBmZTJmMGUxYWZmNjg0ZTc5YzhkYWFlMTY1NzJkOARncG9zAzQwBGl0A2Jpbmc-?back=http%3A%2F%2Fimages.search.yahoo.com%2Fsearch%2Fimages%3Fp%3D7950%2Bvga%2Bpower%2Bpins%26fr%3Dmcafee%26fr2%3Dpiv-web%26tab%3Dorganic%26ri%3D40&w=800&h=600&imgurl=i48.tinypic.com%2Ffursi8.jpg&rurl=http%3A%2F%2Fwww.gamexeon.com%2Fforum%2Fhardware-article%2F93943-review-his-hd-7950-iceq-cocok-untuk-yang-suka-overclock.html&size=239.2KB&name=Konektifitas+yang+di+gunakan+oleh+%3Cb%3EVGA+%3C%2Fb%3Eini+cukup+lengkap+bahkan+agan+...&p=7950+vga+power+pins&oid=110fe2f0e1aff684e79c8daae16572d8&fr2=piv-web&fr=mcafee&tt=Konektifitas+yang+di+gunakan+oleh+%3Cb%3EVGA+%3C%2Fb%3Eini+cukup+lengkap+bahkan+agan+...&b=0&ni=96&no=40&ts=&tab=organic&sigr=13hh86gcl&sigb=13atthjbd&sigi=10q7fh2n2&.crumb=nACcx5MNzi/&fr=mcafee

Yes you have to connect those, they are the pcie power connectors. As far as I know, (maybe someone can correct me if i'm wrong) pcie power connectors are the card's main source of power and molex on the riser is just there so the card doesn't draw extra power from the motherboard.

[rolyasm]

Oh man, I am really, really sorry, but here goes the last question. So my red VGA outputs on the Power Supply are 8 pin, I have 6 of those, 7 if you include the CPU2. I have one SATA 6 pin left on the power supply.
So I need to 7 cables to go from my 8 pin on the Power supply to the 6 pins on my Video Card. Then I am assuming I can use the 6 pin SATA and connect it directly to the remaining 6 pin on my Video card. I am hoping the PSU is really a 6+2 connector and I can  just not use the extra two pins. If not...
After some research I found these cables. Is this what I need?
 CableHero Dual 8-Pin (6+2 Pin) PCI-Express 2.0 Power Adapter Converter Cable from 2x 4-Pin Molex for Gaming Video Cards:

http://www.amazon.com/CableHero-PCI-Express-Adapter-Converter-Gaming/dp/B0032MT0OU/ref=sr_1_1?s=electronics&ie=UTF8&qid=1388775050&sr=1-1&keywords=8-Pin%286%2B2%29+PCI+Express+2.0+Conversion+Cable

Sorry to be such a dolt
Thanks
Roly

[YourNerdyJoe]

Plug cables into the sockets they're meant to be in. Plug to 6pin pcie power into the card, the molex to the riser, and the 4 pin cpu power should be pluged into the motherboard (or 2 - 4pin if there are 8pins for the cpu power on the mobo). The cpu power connector will NOT fit into the card. If you look very closely at the connectors, you'll see that some pins are square while the corresponding pin on the other in house shaped.

If you have extra molex connectors, i've seen adapters that convert molex to pcie power.
http://www.amazon.com/HDE-PCI-Express-Pin-Molex/dp/B002CZANA8

What power supply are you using? The best way may be to just get a second psu to run some of the cards.

EDIT: didn't see your last edit before posting. Since there are 2 - 6pin pcie power connectors on the 7950 I would suggest the adapter I posted instead. When I was googling, I saw a thread saying molex wasn't made for the high current that the cards draw. So I would recommend the dual molex to 1 pcie over the 2 molex to 2 pcie 8pin. Once again a second power supply might be needed if one isn't sufficient.

[rolyasm]

Again, such a Noob. Sorry. I shouldn't be relying on you all to pick up my slack.
My PSU is an EVGA 1300G2. The VGA are 6+2 pin PCI-E, so that solves some of the issue.
I still need 2 more. There isn't any way to use the extra SATA 6 pin or CPU2 8 pin connectors on the power supply?
Here is my card:
 http://www.newegg.com/Product/Product.aspx?Item=N82E16817438011
and a picture of the back:
http://images.search.yahoo.com/images/view;_ylt=A0PDoTH3DsdSS3EA26uJzbkF;_ylu=X3oDMTIzczBxbzBtBHNlYwNzcgRzbGsDaW1nBG9pZAM0OWZmZWY4NTFjNGFlZjhhYTYzMmY5NWY1MTNkMWQ3YwRncG9zAzEwBGl0A2Jpbmc-?back=http%3A%2F%2Fimages.search.yahoo.com%2Fsearch%2Fimages%3Fp%3DEVGA%2B1300%2Bg2%26fr%3Dmcafee%26fr2%3Dpiv-web%26tab%3Dorganic%26ri%3D10&w=600&h=600&imgurl=www.xtremehardware.com%2Fimages%2Fstories%2FEvga%2Fnews%2FEVGA_SuperNOVA_1300_G2_02.jpg&rurl=http%3A%2F%2Fwww.xtremehardware.com%2Fnews%2Fhardware%2Fevga-annuncia-l-alimentatore-supernova-1300-g2-201306198790%2F&size=61.9KB&name=La+serie+SuperNOVA+%EE%80%80G2%EE%80%81+di+%EE%80%80EVGA%EE%80%81+si+espande+con+l%26%2339%3Barrivo+dell%26%2339%3Balimentatore+%EE%80%801300%EE%80%81+%EE%80%80G2%EE%80%81%2C+da+1300W%2C+affiancandosi+al+modello+presenta+da+1000W.+Il+design&p=EVGA+1300+g2&oid=49ffef851c4aef8aa632f95f513d1d7c&fr2=piv-web&fr=mcafee&tt=La+serie+SuperNOVA+%EE%80%80G2%EE%80%81+di+%EE%80%80EVGA%EE%80%81+si+espande+con+l%26%2339%3Barrivo+dell%26%2339%3Balimentatore+%EE%80%801300%EE%80%81+%EE%80%80G2%EE%80%81%2C+da+1300W%2C+affiancandosi+al+modello+presenta+da+1000W.+Il+design&b=0&ni=96&no=10&ts=&tab=organic&sigr=138t7h1cn&sigb=133c0n5n2&sigi=12d0rgf1r&.crumb=nACcx5MNzi/&fr=mcafee

[rolyasm]

Update:
So 2 of my 8 pin cables are split to double 6 pin. If I use the (6) 6+2 output pins on the PSU, 2 cards have full power (2 cords from 8 pin to 6 pin) while the other 2 cards would have a split power (8 pin to 6pin/6pin split). If I remember reading correctly, each 8 pin provides 150 watts, 6 pins are 75. Does anyone know when I use the provided cords that connect 8 pin to 6 pin if that down regulates the power to 75, so in essence each card is getting 150 total? And does anyone know if using the provided cables that are 8 pin power side and dual 6 pin on the card side if that will be enough power, maybe 150 total?
Thanks.

[YourNerdyJoe]

1300w should be plenty to power the cards.
You can try searching for sata power to pcie adapters
Found this: http://www.newegg.com/Product/Product.aspx?gclid=CK_TjZDh4rsCFYNxOgod0F8Alw&Item=N82E16812400105&nm_mc=KNC-GoogleAdwords&cm_mmc=KNC-GoogleAdwords-_-pla-_-SATA+%2f+eSATA+Cables-_-N82E16812400105&ef_id=UNyOYAAASSUvBQK4:20140103193937:s

Once again, if I had to use something like this, I would get the 2 sata power to pcie because gpus draw a lot of power compared to hard drives these were meant to power.
You should be okay since you have to molex adapter on the riser.

I personally don't like messing with the power to much b/c if the psu goes you'l be making more s'mores than bitcoin.
Since you have a REALLY nice psu with enough juice (1300w) I wouldn't be concerned about this just thought I'd put a little warning up.

I haven't had to do this since I currently only have 1 6870 that mines when i'm not using my computer, but have enough experience w/ pc building and mining to help you.
Saw this a while back maybe it'll be some help or just a nice read if you're into that kinda thing: http://blog.zorinaq.com/?e=42

EDIT: WHY YOU POST WHENEVER IM WRITING ARRRRG!!!!! jk no worry
I think I remember reading that too, at least the 6pin - 75w part.
If thats the case see if there is an adapter otherwise use the sata adapter linked above.
Found some that are 6pin to dual 6pin, but since it starts out as a 6 pin pcie I wouldn't trust it to supply enough power in your case.

EDIT2: just found this: https://bitcointalk.org/index.php?topic=84724.msg936069#msg936069
Since you have 6+2pin on your psu the 6pin to dual 6pin may work.
http://www.newegg.com/Product/Product.aspx?gclid=CKDV6aPp4rsCFW9nOgodnEUAaQ&Item=N82E16812198016&nm_mc=KNC-GoogleAdwords&cm_mmc=KNC-GoogleAdwords-_-pla-_-Internal+Power+Cables-_-N82E16812198016&ef_id=UNyOYAAASSUvBQK4:20140103201606:s
Reviews say it works.