Beware of using 6-pin to 8-pin PCI-E adapters.

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JCNiest5

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Okay, so I have two PSUs that was killed by a GTX 770 when using 6-pin to 8-pin PCI-E adapters. Granted, both are just 500W with only one PCI-E 6-pin each and so when I was testing my PC consisted of an Asus X99 Deluxe/U3.1 and 5820K with an EVGA Classified GTX 770 4GB (which needs two 8-pin PCI-e plugs), I used one 6-pin to 8-pin adapter and the other 8-pin requirement, I used the 4-pin molex to 6-pin PCI-E, then connect the 6-pin to 8-pin adapter to that, so I finally had two 8-pin PCI-E wires set for my GTX 770.

On one test, I was just using AID64 and ran System Stability Test overnight. GPU option wasn't checked. The PC was dead in the morning. I was like, "Strange. Why did it turn itself off?" I tried to turn it on, nothing. I could still see that there is power coming because the "standby LED" is still lit. I unplugged the power cord from the PSU for 30 seconds. Plugged it back in and turn it on. It only flickered for about 1/4 of a second, then nothing afterward. I'd only get the flicker and nothing else, so I tried the second PSU the same way as described above. Remember, both of these PSUs only have one 6-pin PCI-E wire set.

This time, I tried running Furmark GPU Burn-in just for the sake of it. Within 15 seconds, I heard a pop plus saw a spark inside the PSU box. A little smoke rose and the usual strong circuit burn smell followed. That PSU is completely dead. Not a flicker at all like the first one. So, my finding? Don't ever use 6-pin to 8-pin adapters (or molex to 6-pin then to 8-pin) again, especially if your PSU is somewhat weak to start with.

After those two dead PSUs, I tried my 700W that has two 8-pin PCI-E plugs and ran Furmark again, works fine. No problem.

I think the GTX 770 may have drawn too much power and the two PSUs couldn't handle it or something, thus killing them in the process.

I may be completely wrong, so take the advice with lots of grains of salt.
 
Sound as much like you abusing the power adapters situation (4-pin Molex -> 6-Pin PCIe -> 8-Pin PCIe) as it does a bad or underpowered PSU.

Get a PSU with the plugs you need to run the stuff you want to run - Exceptions (IE adapters) aren't smart for running one's equipment.
 
I have to ask.. what "500W PSU" were you using?.. I hardly doubt you will kill a PSU by using molex to PCI-E power adapters then 6 pin to 8 pin.. have you overclocked your processor?. you probably know how much power hog can be haswell-E chips when overclocked which can be a big problems with crappy PSUs with low +12v Amperage..
 
I think because you had two sources of 8-pin power differing in resistance (maybe even fed from different PSU rails), one of the inputs could have been feeding power to the other AND the card.

One thing I always do after I plug a PSU connector somewhere is to push the individual wires a bit just in case one of the leads isn't quite reaching far enough.
 
Araxie said:
I have to ask.. what "500W PSU" were you using?
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This. I suspect low quality psus that don't have more connections for a reason.

I love 800watt super quality very much wow! psus that only have 1 6+2 pin. Ensuring that no one gets even close to trying to pull 800 watts from them.
 
I generally find those 6-pin to 8-pin adapters don't provide enough power so the cards are flakey, never had one blow anything up. I think your issue might be the combination of cheap power supplies and too many adapters.

I personally gave up using any time of PCI-E adapter based on poor experiences but none of them blew a power supply.
 
System was not overclocked. Everything was at stock setting. The PSUs were those cheapy ones from the local MC store. One was a Diablotek and the other one was a Solid Gear. As stated, both are 500W with just one 6-pin plug each. They run my other lower end PCs fine, in case you are wondering.
 
JCNiest5 said:
I used the 4-pin molex to 6-pin PCI-E, then connect the 6-pin to 8-pin adapter to that, so I finally had two 8-pin PCI-E wires set for my GTX 770.
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Talk about stretching the limits. This was seriously a terrible idea.
 
JCNiest5 said:
The PSUs were those cheapy ones from the local MC store. One was a Diablotek and the other one was a Solid Gear. As stated, both are 500W with just one 6-pin plug each. They run my other lower end PCs fine, in case you are wondering.
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There you got then.. never, never use cheap PSUs.. PSU its one of the pc components where you have to spend without hesitate thinking about it.. I still don't understand how in the word a guy can build a high end X99 machine.. and then just use a crappy PSUs.. a cheap 50$ EVGA PSU can save a lot of troubles even for cheap and tight budget machines..
 
Araxie said:
There you got then.. never, never use cheap PSUs.. PSU its one of the pc components where you have to spend without hesitate thinking about it.. I still don't understand how in the word a guy can build a high end X99 machine.. and then just use a crappy PSUs.. a cheap 50$ EVGA PSU can save a lot of troubles even for cheap and tight budget machines..
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Good point. It was only used for the testing stage only, though. When the system goes in a case, I'll put a good brand name psu in there.
 
The moment you put Diablotek and other off brand PSUs in your system is the moment you're asking for something to die. Realistically those PSUs were probably capable of 200-300 watts on the 12v rail, at most.
 
My usual thinking is that if your current PSU doesn't have the hookups you need just buy a new PSU. Not worth the risk.
 
I've always felt video card manufacturers were misleading people by including those adapters with their gpus without an explanation. There are a few rare situations where using one of those adapters is acceptable, such as a high end psu that was released prior to the pci-e 8 pin standard being released. Granted, that was quite some time ago now, but if you had new old-stock laying around, that should work just fine.

But situations like that are extremely rare. If anything, the adapters should include a warning, stating that they are only intended for limited use, and to verify the power supply is appropriately rated for the graphics card.
 
Molex -> PCIe is where you went wrong. Molex only has one 12v line.

And a 500 watt powersupply on a rig like that... Even though it probably should of been ok.
 
No. The problem was the $20 psu, without a doubt. A sticker that says 500watts does not make it a 500watt psu. Put that same adapter on a decent quality psu and there won't be a problem.

I don't know how people still don't get this with all the info out there.

Title needs to be changed to, "Beware of using trash psus."
 
Kardonxt said:
No. The problem was the $20 psu, without a doubt. A sticker that says 500watts does not make it a 500watt psu. Put that same adapter on a decent quality psu and there won't be a problem.

I don't know how people still don't get this with all the info out there.

Title needs to be changed to, "Beware of using trash psus."
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This.
 
This reminds me of the guy on reddit who powered a 295X2 with a 6 pin -> 2x 8 pin splitter.

Yes, he plugged a 500+W GPU into a power connector rated for 75W. Bad things happened.

Stop cheaping out on your power supplies guys.
 
Tsumi said:
This.
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this +2

Rizen said:
This reminds me of the guy on reddit who powered a 295X2 with a 6 pin -> 2x 8 pin splitter.

Yes, he plugged a 500+W GPU into a power connector rated for 75W. Bad things happened.

Stop cheaping out on your power supplies guys.
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oh man.. that's crap... :eek::eek::eek: things weren't as good as the guy thought it could be I guess.
 
I remember a few years back, I put an "Ultra" 800 watt PSU in my system. Worked all of 3 months, and then "poof".. Sparked and died when I tried to start it up one day. My 600w Corsair has far more power on the 12v rail, and a much higher efficiency on power than that 800 watter did!
 
Rav3n said:
Talk about stretching the limits. This was seriously a terrible idea.
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I think he was lucky the wires didn't melt and catch something on fire...

Araxie said:
There you got then.. never, never use cheap PSUs.. PSU its one of the pc components where you have to spend without hesitate thinking about it.. I still don't understand how in the word a guy can build a high end X99 machine.. and then just use a crappy PSUs.. a cheap 50$ EVGA PSU can save a lot of troubles even for cheap and tight budget machines..
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Indeed. PSU is the one thing you should not cheap out on. When it fails it could cause all the connected hardware to die with it, or at worst cause a fire. That doesn't mean you have to buy an OMG $300 PSU, like you said. Just pay attention to who the OEM supplier is and the amperage on the +12V rail(s).

CrazyRob said:
I've always felt video card manufacturers were misleading people by including those adapters with their gpus without an explanation. There are a few rare situations where using one of those adapters is acceptable, such as a high end psu that was released prior to the pci-e 8 pin standard being released. Granted, that was quite some time ago now, but if you had new old-stock laying around, that should work just fine.

But situations like that are extremely rare. If anything, the adapters should include a warning, stating that they are only intended for limited use, and to verify the power supply is appropriately rated for the graphics card.
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I have noticed nowadays that video cards are now including a 2x 6-pin to 8-pin PCI-E power adapter instead of just 1x 6-pin to 1x 8-pin. It is a good solution to make it just a little more idiot proof. However they still need to stop with the Molex adapters. Those are just asking for trouble.

txsizzler said:
I remember a few years back, I put an "Ultra" 800 watt PSU in my system. Worked all of 3 months, and then "poof".. Sparked and died when I tried to start it up one day. My 600w Corsair has far more power on the 12v rail, and a much higher efficiency on power than that 800 watter did!
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Always pay attention to the amperage rating on the +12V rail(s) over total power rating first and foremost. It is a good initial indicator on whether or not it is a good PSU.
 
JCNiest5 said:
System was not overclocked. Everything was at stock setting. The PSUs were those cheapy ones from the local MC store. One was a Diablotek and the other one was a Solid Gear. As stated, both are 500W with just one 6-pin plug each. They run my other lower end PCs fine, in case you are wondering.
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As others have stated, the problem is crap PSUs that dont give rated power and can damage components when they die.
You have been lucky..
I'm glad you are looking at a better one.
 
Problem is your cheap 500W PSUs, not the plug. Lucky you didn't fry some hardware.
 
JCNiest5 said:
Okay, so I have two PSUs that was killed by a GTX 770 when using 6-pin to 8-pin PCI-E adapters. Granted, both are just 500W with only one PCI-E 6-pin each and so when I was testing my PC consisted of an Asus X99 Deluxe/U3.1 and 5820K with an EVGA Classified GTX 770 4GB (which needs two 8-pin PCI-e plugs), I used one 6-pin to 8-pin adapter and the other 8-pin requirement, I used the 4-pin molex to 6-pin PCI-E, then connect the 6-pin to 8-pin adapter to that, so I finally had two 8-pin PCI-E wires set for my GTX 770.
.....

I think the GTX 770 may have drawn too much power and the two PSUs couldn't handle it or something, thus killing them in the process.
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Ya. You definitely killed the PSU's by overloading them. You likely overloaded one of the 12v rails. At most, this shit PSU should have been used for a test boot with very little load. Even then I wouldn't dare using such a heap of shit on expensive new equipment unless I was absolutely desparate.

TBH, I'm surprised the thing didn't simply catch fire. There is a reason those PCIe power plugs have 3 or 4 wires carrying 12v+ and 3 or 4 wires carrying ground. The amount of current a wire can carry is dependent upon the thickness of the wire. When the wires aren't thick, you run mulitiple wires to carry the same load. This isn't even taking into consideration the connectors themselves, which also have their limits. The wires and connectors usually have some headroom on them, but usually not enough to use multiple adapters.

You used a 4pin molex adapter that has only one 12v wire on it per plug(yellow usually), to a 6pin PCIe that has 3x12v wires, then to an 8 pin adapter that has 4x12v wires on it. So you had a high end graphics card sucking down power across 2 wires and 1 plug (at the 4pin to 6pin adapter). You might have gotten away with the one adapter, but daisy chaining like you did is a big no-no.

You know those public service announcements or scenes out of movies where there are 50 things plugged into 1 outlet and it catches fire? That's exactly what you did here. You got lucky.
outlet-overload-250x150.jpg
 
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xorbe said:
3 for power, 3 for ground, 2 for cable sense.
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Thank you for the correction. However, the point remains the same. There are multiple wires to carry the load. When you use adapters you are putting more current through less wires and sometimes what wires you do have are going through a single pin on one end of the adapter cable.
 
This also reminds me of when I was a kid, doing some mowing and weedeating job for my mother's business. I was using an electric weedeater, and ran out of cord with the one extension I was using. So, I thought, "why not daisy chain the extension cords for an ultra long reach?".

Needless to say, the results were disastrous. The weedeater caught on fire, and completely melted the internals. Lesson learned!
 
txsizzler said:
This also reminds me of when I was a kid, doing some mowing and weedeating job for my mother's business. I was using an electric weedeater, and ran out of cord with the one extension I was using. So, I thought, "why not daisy chain the extension cords for an ultra long reach?".

Needless to say, the results were disastrous. The weedeater caught on fire, and completely melted the internals. Lesson learned!
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Longer cord lowers the power delivered to the weedeater, that doesn't make any sense. At best a few volts dropped. Weedeater is not a super hungry device perhaps 700-800 watts.
 
Hey guys. Be wary of putting diesel into your car if it says Unleaded Fuel Only. I know it's not the recommended power source, but they both come from nozzles so it has to be fine, right? Wrong. Now I can't drive to Taco Bell.
 
JCNiest5 said:
It may have been...there are adapters for the purpose, so I thought I'd put it to good use! :D
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Not in the way you are thinking of.

Those 4 pins are not used for supplying that much voltage+amperage, I don't think ANY 4pin will support that spec.

6 pin can support the voltage+amperage requirements of some 8pin devices but you have to check to make sure the PSU first can support this.

Never split a plug more than once or convert more than once, if you need to you should get another PSU.
 
Rizen said:
This reminds me of the guy on reddit who powered a 295X2 with a 6 pin -> 2x 8 pin splitter.

Yes, he plugged a 500+W GPU into a power connector rated for 75W. Bad things happened.

Stop cheaping out on your power supplies guys.
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I need a link for this for the lols.
 
JCNiest5 said:
Insert completely piss poor advice

I may be completely wrong, so take the advice with lots of grains of salt.
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Yeah, yeah you are completely wrong. You did shit completely half ass and now you are trying to "warn" people that the sky is falling! Use the correct components and you won't have any problems.
 
xorbe said:
Longer cord lowers the power delivered to the weedeater, that doesn't make any sense. At best a few volts dropped. Weedeater is not a super hungry device perhaps 700-800 watts.
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wrong it increase resistance and in turn multiply that by the amps drawn and you end up with a much higher load....thats why it melted :D
Same thing will happen to a well pump for example if using to small of gauge wire....it burns up the pump well before it should and will void warranty

edit: might have this slightly incorrect but correct in idea lol It is a little confusing but when the voltage drops from the length of the wire and the size of the wire being to small it increase's resistance...and when that happens things start to heat up which makes matters even worse until something burns
 
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Use as a blunt force weapon is about the only thing I'd recommend a Diablotek PSU for, and even then, there are better and cheaper options available.
 
primetime said:
wrong it increase resistance and in turn multiply that by the amps drawn and you end up with a much higher load
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No, the total R is up, which causes current to fall ... but as the AC motor falls out of its efficiency band, it struggles due to insufficient voltage and heats up. Similar to lowering line Hz from 60 to 50.
 
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