[SOLVED] Are Dual 6-Pin to 8-Pin Cables Safe?

[BlookyDJ]

I want to cram a GTX 1080 Into my PC, But i don't have a 8 Pin cable on my PSU, despite the fact it's rated for 800W.
So i went looking on eBay, and that's when i learned these cables exist, I've heard mixed opinions on them so I'm just here for a straight answer.

 

[kanewolf]

I want to cram a GTX 1080 Into my PC, But i don't have a 8 Pin cable on my PSU, despite the fact it's rated for 800W.
So i went looking on eBay, and that's when i learned these cables exist, I've heard mixed opinions on them so I'm just here for a straight answer.

Straight answer is "If your power supply doesn't have the proper cables than it isn't designed to support what you want to do". Long answer is, you "800W" power supply is probably a cheap unit that over estimates the wattage it will support. Will a dual 6-pin to single 8-pin adapter melt down and start a fire? Who knows. All sorts of cheap junk is sold, especially on E-Bay.

 

[Joseph_138]

Dual 6-pin to single 8-pin is done all the time without a problem.

 

[Karadjgne]

Umm my question would be why doesn't an 800w psu have a single 6+2pin pcie. In most ways, that simply means it's not a 800w psu, regardless of claims, since even a decent 450w has at least a 6+2pin and 6pin pcie.

Basic rule of thumb, no matter claimed size, is that if you need to use adapters, the psu is not built to handle that gpu.

Regarding the adapters themselves, that's entirely dependent on who built the adapter. Reputable companies like Molex or CableMod will use the correct sized pins, correct sized wiring etc but consequently cost more. The 'El Cheapo' stuff found on eBay often as not doesn't, it's just wires and pins bought as cheap as possible, which means smaller gage, which can be a hazard.

 

[DSzymborski]

The best information to provide would be what your current PSU is.

 

[spentshells]

you are the person who posted this, your system is based on a hp z800 with the stock psu?

 

[BlookyDJ]

Actually, It's just a modified Pre-Built on eBay, a Dell T3600 Precision iirc, I stuck in a GTX 760 long ago but I've been looking to upgrade, I can probably take a minute or two to have a look at whatever company made the PSU.

 

[DSzymborski]

Actually, It's just a modified Pre-Built on eBay, a Dell T3600 Precision iirc, I stuck in a GTX 760 long ago but I've been looking to upgrade, I can probably take a minute or two to have a look at whatever company made the PSU.

The good news is that Dell tends to put pretty decent OEM PSUs in their PCs, especially the workstation ones.

However, this is also an extremely old PSU at this point. If I could verify this was one of their good PSUs -- and it's likely -- dual 6-pin to 8-pin is something I might have, if not recommended, at least not specifically cautioned against, if the adapter was from a good source and the PSU was a new one.

I would not do this at all. And honestly, I don't think I would if you had the 8-pin plugs, either. If you want to do this, you'd be smart to replace the PSU, the ease of which depending on if this is one that uses the 24-pin ATX cable and 4-pin or 8-pin CPU cables. Dell's not universal in what their boards use, so you'll have to actually investigate this.

 

[BlookyDJ]

Since the Proprietary PSU is sized to fit in the incredibly small area of the Computer, The best option is either to start a new build from scratch, or buy a new case and PSU so i can actually make this work.

 

[DSzymborski]

Since the PSU is sized to fit in the incredibly small area of the Computer, The best option is either to start a new build from scratch, or buy a new case and PSU so i can actually make this work.

Honestly, if this PC is so old that you once upgraded to a GTX 760, which was released in 2013, it might not really be able to take advantage of a GTX 1070 anyway. Though it's hard to say for sure as you really haven't told us much about your PC at all.

 

[BlookyDJ]

It uses an Intel Xeon E5-1620 0, 3.6GHz, It supports PCIe Gen 3.0, Although I'm unsure as to whatever else is required besides a capable PSU I'm unsure of

 

[ohio_buckeye]

GPU Power Connectors Explained [Simple Answer] - GPU Mag

All GPU power connectors can be difficult to understand. Here's a simple explanation of the 6-pin and 8-pin connectors and how they differ.

www.gpumag.com

There’s guide that might be more helpful. According to that and some other information I’ve heard, a 6 pin connector is a 75 watt connector. 8 pin is 150. IF your adapter is of good quality, I would think 2 6 pin to a single 8 pin adapter would be safe. But not the single 6 to 8 pin. Those kinds of adapters, especially cheap ones you could be talking fire. Some guys say the 2 extra pins are grounding pins. Perhaps, but better safe than sorry.

The sage idea is to get a power supply that has the needed cables if possible already.

 

[BlookyDJ]

So, what i've learned today from this thread, is that my PSU probably isn't rated high enough for an 8 Pin connector, and that I am probably not a very smart person.

 

[ohio_buckeye]

Don't say you aren't smart, we all have to learn. I learned once the hard way by frying IDE ports back in the day by using a cheaper power supply from Ebay. We are just trying to save you from learning the way we did.

But if you have two 6 pins, you could probably run a gtx 1660 super. Looks like they can be found around 400 on ebay, which is sad considering they sold msrp for 220-230.

A card like this could work too.

https://www.ebay.com/itm/224518151812?hash=item3446531e84:g:ttgAAOSwaihgy7pI&LH_BIN=1

Not quite up to the GTX 1080, but at 1080p that card should still be a beast. And you should be able to run one with a single 8 pin using an adapter from dual 6 pins to single 8 pins. You'd just hate to try to use other adapters and blow your card sky high.

 

[BlookyDJ]

Don't say you aren't smart, we all have to learn. I learned once the hard way by frying IDE ports back in the day by using a cheaper power supply from Ebay. We are just trying to save you from learning the way we did.

But if you have two 6 pins, you could probably run a gtx 1660 super. Looks like they can be found around 400 on ebay, which is sad considering they sold msrp for 220-230.

A card like this could work too.

https://www.ebay.com/itm/224518151812?hash=item3446531e84:g:ttgAAOSwaihgy7pI&LH_BIN=1

Not quite up to the GTX 1080, but at 1080p that card should still be a beast. And you should be able to run one with a single 8 pin using an adapter from dual 6 pins to single 8 pins. You'd just hate to try to use other adapters and blow your card sky high.

I think I'll try to get a 1060 or a 1650 Super just to stay safe, Maybe a 980 If i find a lucky deal.

 

[ohio_buckeye]

There are 980ti cards out there as well, but they are a beast of a card and very power hungry. I think they will probably leave driver support in a year or so as well, which means no game optimizations etc.

Here's a cheaper for today's prices 1650 super.

https://www.ebay.com/itm/255041857869?hash=item3b61ade94d:g:HOYAAOSwVX5g06en&LH_BIN=1

Requires a 6 pin, but if you have that you should be good. Looks like performance is comparable to an RX 580.

 

[Karadjgne]

6pin is 2x hots, 3x grounds and a sense pin. The sense pin might go To ground, but it isn't a ground. It's a pin that tells the gpu it's a 6pin power connector. An 8pin has 3x hots, 3x grounds and 2x sense pins. It takes both the sense to make the gpu understand its an 8pin not a 6pin power, it's a safety precaution to prevent higher TDP gpus from over-drawing power on a smaller connection or ppl using jack-rabbit wiring/adapters to fake power draw from sub-standard psus.

 

[BlookyDJ]

So I just made a discovery while having a look in my PC.

1. The PSU is 685W
2. The Dual 6-Pin connectors were actually plugged into an 8-Pin Socket a small board where the PSU was connected, Meaning i can put in an 8-Pin GPU.
3. I Probably should have done this before actually making this forum.

https://imgur.com/a/d4R7sDJ

View: https://imgur.com/a/d4R7sDJ

 

[Karadjgne]

That's not an 8pin, regardless of the actual pin count. ANYthing attached as such, whether it's a daughter board or modular connector is and should be considered no different than a simple connection. It's just a plug. The only thing that matters is what's on the other end, namely 2x 6pin pcie. Those can be adapted to a 8pin pcie, but don't try using that board connector. There's absolutely no telling the polarity without testing, and could easily be backwards to pcie needs using a generic male-female 8pin pcie wire.

 

[BlookyDJ]

I Should note that the blurred text above the plug is titled as "POWER_VGA2", an 8-Pin Male to 8-Pin male plug should work just fine if it was able to run a 8-Pin male to x2 6-Pin Males.
Sorry if i misunderstood your message.

 

[ohio_buckeye]

One thing I would point out as well, looks like you have a standard hard drive in there. When you can, pop a 1tb ssd in there. It will cost around 100 dollars US, but that upgrade alone will make that pc feel brand new.

 

[BlookyDJ]

One thing I would point out as well, looks like you have a standard hard drive in there. When you can, pop a 1tb ssd in there. It will cost around 100 dollars US, but that upgrade alone will make that pc feel brand new.

Yeah, I have an SSD In my laptop and the boot speed is unreal.

 

[Karadjgne]

I'm saying it's not an 8pin on that board. It could be a 2pin or a 12pin or a 100pin, doesn't make a difference, it's just a plug. It's not a pcie nor EPS or molex or anything else. It's just a connector that happens to have 8 pins. You should Not Assume it's anything standard, some of those pins will be hots, some are grounds, and for all you know there could be 3.3v or 5v on one of those pins. What's important is where those pins end up, not where they start. Pcie are laid out in specific polarity, EPS are the opposite layout and those are determined by where the wires plug into the back of the connector, not where they start from. If you assume you can just use an 8pin extension, you may very well put power into ground and/or ground into power and blow up the gpu.

Or the psu. Or the motherboard. Or the cpu. Depends on how well its protected and whether those protections actually work.

You have a modular cable with a modular plug on 1 end and 2x 6pin pcie on the other. That's all. Not an 8pin on one end and 2x 6pin on the other. Forget that 8pin even counts as anything more than just a modular plug.

 

[ohio_buckeye]

If you were to try to install a standard ATX power supply, would this cable work?

https://www.ebay.com/itm/12-Inch-24...e=STRK:MEBIDX:IT&_trksid=p2060353.m1438.l2649