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Wiring up Dual 980ti Hydro Copper 8x6 pin connections

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SwartHack

Babysitter for OCF Lounge Day Care, Still a bad-as
Joined
Apr 3, 2015
Location
Planet Earth
So I find myself on the precipice of absolute greatness or utter failure...
I have decided, with some prodding by Lochekey, to make my own cables, kinda, for Father Time. (sig.)
( I got a bunch of the individually pre-sleeved wires)

So it should be pretty easy and straight forward, except where you have to go two-wires to one pin.
I couldn't find any pre-sleeved wires like this, but I can overcome this...
And I have the adapter figured out for the mobo 18x10 to 24 conversion, I think...

This brings me to looking at the 8x6 pin PCIe connections for the gCards and my question.
part4 (5).JPG

I have a beast of a PSU
G2-back.jpg

and was thinking that instead of running the 6-pin piggybacked off the 8-pin for each gCard..
Like we see on all stock psu cables. (and avoiding having to make this pig-tail cable)...
IMG_2185.JPG

That I could run all connections independent off of their own port on the PSU?!?
(God knows there are enough)

I stumbled onto this idea while researching the wiring/pin-outs/etc...
Somewhere it stated that the 6-pin was added solely to provide additional power needed by newer cards and overclocking...
It seemed to me if this was the case, not sharing the juice with the 8-pin would be beneficial?!?

So is there a difference/advantage/disadvantage between the 8 and 6 pin sharing the juice off one PSU evga port using a pig-tailed connector...
or wiring each one independent to the psu..?


Especially considering I plan on pushing this set-up as far as it will go.

Thanks for the expertise!

Luego
 

Blaylock

"That Backfired" Senior Member
Joined
Jun 5, 2013
Location
Go Blue!
Well I'll give it a shot, though I'm no electrical engineer.

In short I believe no benefit (especially if it's a single rail).

My reasoning and long answer. Unless you are approaching the max wattage for that individual rail I don't think pulling the 6 pin to a different plug will help. Nor will you approach the max rating for the cables. If this were an older underpowered PSU then yes. The old "balancing" of the rails comes to mind. But in this case, the size and quality of that PSU and the draw of 2x 980tis should be child's play. He'll I'd venture to bet you don't even reach maximum efficiency. LoL An after thought: You would also need to be able to determine which other plug would be on a separate rail, assuming this PSU wasn't single rail that is.
 

Silver_Pharaoh

Likes the big ones n00b Member
Joined
Sep 7, 2013
Your PSU, EVGA 1600 G2 is a single rail unit, thus getting rid of the "piggyback" accomplishes nothing because each one of those VGA outputs, "VGA1, VGA2" etc, all draw from the same 12v pool.

All you would be doing is adding extra wiring in your case.


Now, you can make your own piggyback wires using a thicker gauge wire if you want but you shouldn't need too. :)
 

caddi daddi

Godzilla to ant hills
Joined
Jan 10, 2012
for performance you're not really going to gain anything but, to my eyes the piggybacked cables look like crap so for my fully exposed rig it is all split, 2 6 pin pcie and 2 8 pin pcie cables.
 

Lochekey

Senior Pink Member
Joined
Sep 13, 2015
I would wire each one independently. As silver said it is a single rail psu so no worries on which ports you use. Silver also mentioned the extra cable runs but as caddi said I feel that looks better than the cables with the split 6 pins. One advantage I see is that by splitting the 6 pin into its own wiring run you will reduce the amperage on each individual wire. I doubt this will translate into any real world benefit but it it's at least one positive.
 
OP
SwartHack

SwartHack

Babysitter for OCF Lounge Day Care, Still a bad-as
Joined
Apr 3, 2015
Location
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Thanks Gents...

Silver_Pharaoh said:
...all draw from the same 12v pool.

So yeah, single rail and rail balancing I remember back to researching PSUs and recall some promotional deal exclaiming "No more load balancing..."
It seems that is the standard now, let the PSU deal with balancing in said juice "pool". Which is nice...
Frankly and mostly obviously, I am not worried about my capacity. It will be fun to see how high a draw we can reach though when its all rigged...
Speaking of that, haven't seen either of you, SP or cd, lately slumming in my proj logs. Stop by and leave some disparaging remarks...

On this note, have a decision to make, as I have all these damn cables.
I kinda lean towards cd and the 6 and 8 seperate, with some cleverly placed combs and routing, etc.
I dont mind the pig-tail so much, if done right, but really dont want to make it....

Anyway, more of a thought for other thread.
Thanks for the guidance gentleman, now I can proceed accordingly.

Eskerrik Asko -(That's Basque for "Thank You", for those to lazy to look it up or that simply don't care) ;)
 
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SwartHack

SwartHack

Babysitter for OCF Lounge Day Care, Still a bad-as
Joined
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Please Re-Convene! Ripple Capacitors encountered...

I have encountered another obstacle here and need some guidance again, please...

If you remember the illustrated VGA/PCIe cable in my initial post and discussion regarding the pig-tail:
attachment.php


Well bust apart that cable and surprise!

IMG_2268.JPG

So I get a lead from hangout on this (Thanks Lochekey) about a corsair PSU
http://www.google.com/url?q=http://...sntz=1&usg=AFQjCNEub5U5MvKoUfNcSsgLAv-e6Gr7eQ
And I see this:

corsair_psu.jpg

And I have been wondering about my mobo cable and where those extra wires where going/coming.
After a few minutes, I got this on my mobo cable as well...

IMG_2281.JPG

So TWO things I need to know:

1
-I am not going pig-tail on these and will run a separate 6x cable.
Will I still need/should I use the capacitor on my 6x PCIe cables?


2. ​sorry! not actually gCard topic, but as long as we are talking about ripple control
I am making a short adapter for the psu-side mobo connection 18x + 10x to 24x.
Mine will look better than this
SF_Series1__48880.1463800993.450.800.jpg

I am assuming I should use the capacitors on my rebuilds!
Therefore I can wire the extension just straight 24x to the mobo-side connection.
Here the capacitors are on the mobo-side.
Can I move them to the psu-side of my extension???

But since I am wiring my extension same plug on both ends, just like a stock cable
Does it really matter?

Any ideas? I am just about to dive into this as I finished my first pair of 8x and 6x PCIe cables.
Thanks!
 

Silver_Pharaoh

Likes the big ones n00b Member
Joined
Sep 7, 2013
I'd put them on the GPU cables sure. It'll smooth out any ripples, though EVGA's ripple suppression is usually spot on.

Confused on #2....
You want to move capacitors from the mobo onto your short extension??
 

Lochekey

Senior Pink Member
Joined
Sep 13, 2015
I say leave them off. If you look at the custom sleeved cable sets directly from EVGA they do not contain any capacitors.

If you want to keep them just move them to the psu side of the cable.
 

Blaylock

"That Backfired" Senior Member
Joined
Jun 5, 2013
Location
Go Blue!
^ this. As long as it's wired the same the cap won't care what end of the cable it's on.
 
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SwartHack

SwartHack

Babysitter for OCF Lounge Day Care, Still a bad-as
Joined
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Location
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I'd put them on the GPU cables sure.
I think you see now #2 was on what end of the extension, not the adapter.

OK, if I go with the capacitor on the GPU cables, it currently is on pins 1 & 4 of just the 6x of the pigtail?
Since I am going without pigtail?
Does the capacitor also affect the 8x as well?
 

Blaylock

"That Backfired" Senior Member
Joined
Jun 5, 2013
Location
Go Blue!
as far as leave them off, as well?

I doubt you'll notice a difference to be honest. EVGA's are among the best PSU's according to JonnyGuru. They generally score a 9 or 10 out of 10. Come to think of it, if you added them you could claim yours goes to 11! Lol I seriously doubt it would be noticable.

I think you see now #2 was on what end of the extension, not the adapter.

OK, if I go with the capacitor on the GPU cables, it currently is on pins 1 & 4 of just the 6x of the pigtail?
Since I am going without pigtail?
Does the capacitor also affect the 8x as well?

As far as affecting the 8 & 6 pin I think it would depend on whether it's wired in series or parallel. Man its been years since my electronics classes. Your best bet if you want to truly KNOW what to do is PM Oklahoma_Wolf. I would trust his opinion on this matter over anyones.
 

Lochekey

Senior Pink Member
Joined
Sep 13, 2015
The caps need to be wired in parallel , they will not work in series. As they are wired in parallel on the wires they will affect both the 8 and 6 pin.

If you choose to wire them back in make sure to hook them up the same way they came off. They are probably polarized caps and will be destroyed if they are hooked up backwards.

If it was my system I would just leave them off. If you want to keep them on you could always grab some extra caps and wire them on the 6 pin connectors and use the originals on the 8 pin. Just make sure to match the specs on the original caps.
 
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SwartHack

SwartHack

Babysitter for OCF Lounge Day Care, Still a bad-as
Joined
Apr 3, 2015
Location
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Thanks All!

I am taking the path of least resistance here. (har, get it, electronics joke, har) I am leaving them off!
Based on the approach I am taking with this cable project, if I need/want to add them later it won't be a big deal.
I have a huge grip of capacitors. I got a 645 peice set from Joe Knows Electronics when I was all Arduino OCD.
It does appear the ceramic ones are non-polarized. At least the legs are the same size, and no apparent +/- indicator?

Blaylock said:
EVGA's are among the best PSU's according to JonnyGuru....
...to truly KNOW what to do is PM Oklahoma_Wolf...


For sure, I read this review before I purchased. He barely mentions ripple, and never mentions the capacitors.
http://www.jonnyguru.com/modules.php?name=NDReviews&file=print&reid=391
Does make a mention to the beefy mobo cable though?!

Oklahoma_Wolf! He did the review!I was wondering if he was on OCF or not. Never checked though.
Is jonnyguru associated with us?

Thanks again, hopefully get these all done today...

Cheers

EDIT: no OklahomaWolf on OCF
Edit2: Ah, I get it there is a forum there, durrr
 
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