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ATTENTION!!! anybody needing an 8 pin pci to use your graphics card,I HAVE THE SOLUTION
If you need an 8 pin pci in order to use your graphics card(ex.9800gx2) and only have 6 pin cables,
there is an easy way to make things work without buying a new psu or purchasing an adapter.
With a correct 8pin pci and a correct 6pin pci, the only difference between the two is that on the 8pin
there are two extra ground wires, so the top row(clip side) will be 4 ground wire, and on the bottom
will be 3 +12v and 1 ground wire. to make your 8 pin connector, take your left over 6pin that will not be used(assuming that you have at least 3 cables)and with a razor cut the top 2 right ground plugs away from the rest of the clip, then cut inbetween the 2 that you just cut off so you have 2 seperate ground wires, 1 with a square plug and 1 with angled edges. now plug your 6pin cable into the 8 pin slot on your graphics card so that the right 6 slots are filled and 2 slots are remaining on the left. These 2 slots are where you will plug the 2 ground wires that you just cut off your left over 6pin, plug the square plug into the top slot and the angled edge into the bottom. Thats all you have to do to make it work. I know this may seem confusing the way I wrote this, so if you have any problems let me know and i can make up a diagram and send it to you.
MoneyGuyBK
2.3K Posts
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July 9th, 2008 20:00
Yikes... I would never try this.... :smileysurprised:
Peace
Davet50
14.4K Posts
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July 9th, 2008 21:00
Endrsgm
3 Posts
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July 9th, 2008 21:00
Nice!
Where do i apply the duct tape and how do i use the chocolate bar? j/k
I would probably electrocute myself when i use my tongue to hold down the wires i cut.
Good effort though lukeep.
lukeeep
5 Posts
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July 9th, 2008 23:00
its actually very simple to do and can be done in 5 minutes, and theres really not much butchering.
i didn't want to bother with the adapter in whether it supplies enough power or not, i can't seem to
get a straight answer to use it or not. I was really surprised with the lack of knowledge at the computer
repair places around here.
korrson
592 Posts
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July 10th, 2008 13:00
Thanks for posting this.
While it may no be for everyone its nice to know.
I did a similar butcher job for a proprietary plug on a computerized instrument I use at work because that was my only option.
Astara_
14 Posts
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April 21st, 2012 13:00
WARNING...
This is now 4 years later and there are graphics cards out there (Nvidia 590) that require 2 8-pin connectors not to dot their i's or cross their t's, but because they need a full 25A (or whatever 8-pin connectors are rated for), on each.
This means 1, the above would be really bad -- since a 6 pin is only rated for some fraction (maybe half?) of an 8-pin output.
I have a T-7500 -- with an 1.1KW PS. For graphics it has 2 6-pin and 1 8-pin power cable.. Normally one could buy a cheap connector cable to connect the 2 6's together giving 1 more 8-pin cable. However!, The cabling with the default power supply has 1 of the 6-pin cables coming off of the same "rail" ("Circuit") as the larger 8-pin cable. This means that using those 2 6-pin cables (the only 2 available) will feed the graphics card only 75% of it's rated amperage. When the card goes into a 6-year old video game (Oblivion) that taxes graphics -- it power-cycles the system due to insufficient voltage on the rail supplying both the 8+6 pin adaptors after about 1-2 minutes of play -- very reliably.
It was so bad that with a marginally weaker power supply, even runing the Windows built-in system performance index test would cause the same symptom -- the symptom would be just as though it had been powe-cycled -- cold-reboot.
So if you feed your graphics card merged cables, make sure the parts of the merged cable don't come off the same cable AND make sure that they don't overlap (have same color wiring pair as the other 8-pin. Each rail is usually given a different color-pair of wiring so you can easily tell if wires are on the same circuit or o a different one.
I even had a Dell tech, on a previous system, tell me to connect 2-4-pin molex's together on the same wire, to create a 6 -- something I now know is a no-no for a graphics card while will use both at full draw. When the power supply was replaced in that system, the 1 split brown cable that was double-used to make a 6, was brown around the connector indicating high overheat conditions.
Right now am looking to see if Dell is willing to fix this design flaw...but neither am holding my breath. I may have to have a 2nd powersupply sitting on the outside -- just to power the 2nd leg of the graphics card!....What a pain!
Davet50
14.4K Posts
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April 21st, 2012 20:00
Why is this a Dell design flaw? Almost all card manufacturers don't recommend using adapters to join cables to make a 6 or 8 pin power connector. This is not something that is new.
Astara_
14 Posts
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April 22nd, 2012 02:00
It's dell's top end workstation and I was told that not only should it handle any single card, but was also capable of handling multiple GPU's.
I've been told to join cables together by dell support personnel multiple times.
When I first did it, I follow their instructions to the letter... now I know better -- putting multiple
joiners is only safe if you join from separate sources -- that way you are getting a full load to draw from.
Besides -- there are two 6-pin cables and 1 8-pin cable. One of the 6 pin cables is on the same
power rail.
The connector on the end of that cable is only designed for a video card. So if you put it into any
video card and plug in the 8 pin -- same problem.
The point is that one of their 6-pin video connectors shares the same circuit with the 8-pin --cutting
the available graphics by 25% and resulting in a 33% overdraw of current on 1 circuit.
If dell chose to use a 1 rail design like some have shifted to to prevent these issues, it wouldn't be an issue -- if dell had routed the same circuit cable to the floppies and card reader -- wouldn't have been a problem. But they put both the 6 and 8 pin connectors on a circuit that can only support 1 8-pin connector -- that's a design flaw.
speedstep
9 Legend
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47K Posts
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April 23rd, 2012 09:00
Dell would never recommend cutting cables and joining wires. Its dangerous and potentially fatal to your system and GPU.
Astara_
14 Posts
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April 24th, 2012 16:00
Oh, and you never answer the point of putting the 6-wire and 8-wire graphics power connectors on the same rail -- something that would be a electrical engineers "design no-no" -- i.e. something no qualified designer would ever recommend doing since if both are utilized to *stated* capacity, they would overload the 'rail'. If a product needs the electrical power of an 8 and 2x6's and one of those 6's is
hooked up to the same rail as the 8, that's gonna cause a problem.
I don't see how you can argue against that being a design flaw.
It's NOT that the power supply doesn't have the power.
Nvidia's website states a 365W power draw for the card, which can be supplied (from their website) from a 700W PS. The T7500 with a 1100W power supply should have more than enough -- in reserve -- because it was designed to be able to power 2 high end graphics cards in an SLI config.
That it cannot even handle 1 card due to a cabling-error from the more-than-adequate power-supply, shouldn't be something you should even begin to try to claim is "correct behavior", or "proper design".
Dell did not used to cut corners so much (at least not in the 11+ years that I've been a dell customer/proponent).
I *like* Dell, but I will speak out against wrong practices... (and will defend against wrong accusations)...this wasn't (isn't) good design.
I was surprised to see Dell's top end workstation, now exceeded by their top end gaming machine.
You can order a top end gaming system with a 6-core processor and 1600MHz memory.
The top end you can get on the top-end workstation -- 4-core + 1333MHz. AFAIK, the motherboard limits the memory to 1333,
I don't know if that is something that can be jumpered or what. But the 6-core...That's bad marketing. I have a 6 core in mine now and it uses less power than the older 4 core did (and of course I didn't get it from Dell, they don't offer it -- though I did get my 4-core upgrade, 2nd processor for my server from Dell when they offered it at an excellent price... too rare an event.
Astara_
14 Posts
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April 24th, 2012 16:00
There is no cutting involved, that's your mis-assumption.
You are talking using the equivalent of an extension cord that has 1 output one 1 end, and 2 inputs.
on the other. They are included as stock items with many graphics cards.
Dell might not recommend it, but who is dell? Dell employees in Gold Technical support do.