[SOLVED] Can i power a graphics card with a different computers psu?

scopus

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Hello i want to run a graphics card in an old oem computer that doesnt have a 6 pin connector. Can i use the 6 pin connector from another computer thats sitting right next to it and have both computers running at the same time?

So that older computer will be using its stock psu for all components except the 6pin which it will be getting power from an adjacent computer that will be running
 
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If you simply wanted to have a secondary PSU dedicated to your old PC's GPU, having a secondary PSU would be as simple as simply connecting the two PSU's PS_ON# lines together so both PSUs turn on/off together.

Tapping into a different PC's PSU on the other hand could be problematic since the GPU may not like its VRM having AUX power but no PCIe slot power for much longer than the expected rail-to-rail rise time. If the VRM isn't fully isolating PCIe 12v and AUX 12v, there is also a chance you may end up back-feeding 12v into your other PC through the GPU and end up burning something out.

Karadjgne

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You can, but I'd strongly advise against it. You'd be mixing different voltages and different grounding systems between the pcie slot of one pc and the 12v supply of another pc, all through a single gpu which doesn't exactly keep those voltages seperate. That's a recipe for disaster.

Far better off just using the right psu in the first place. While many OEMs have oddball psu dimensions, you can find others that will fit that do have the right connectors.
 

scopus

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Yes, but I really don't recommend it...
If the other computer isn't powered on the gpu won't work and that could cause all types of funky stuff.


Just swap the psus between the systems.
or get a new one.
or get a molex/sata to pcie adapter.

cant swap the psu as the mobo uses some non standard connectors. No molex just sata but pretty sure thats not a good idea as its psu is very low wattage 240w, and read sata are low wattage connectors. So only option i think is to use the second computers 6pin
 
cant swap the psu as the mobo uses some non standard connectors. No molex just sata but pretty sure thats not a good idea as its psu is very low wattage 240w, and read sata are low wattage connectors. So only option i think is to use the second computers 6pin
I guess, but I would still strongly suggest finding another way.
This is a disaster waiting to happen.

Imagine you just decide
hey let's power off one of the computers
Gpu's probably dead.
 

scopus

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You can, but I'd strongly advise against it. You'd be mixing different voltages and different grounding systems between the pcie slot of one pc and the 12v supply of another pc, all through a single gpu which doesn't exactly keep those voltages seperate. That's a recipe for disaster.

Far better off just using the right psu in the first place. While many OEMs have oddball psu dimensions, you can find others that will fit that do have the right connectors.

id swap the psu but problem is it and the mobo does have some odd non standard connectors. Dont want a disaster so think now perhaps should let this idea go, thanks
 
What kind of computer is this (model name and age).

If this is an older model, getting a secondary PSU is probably a waste of money, it's no guarantee it will work.

Even if you DO make it work (you need a proper relay for this and insight in electric circuits) the GPU may still not work because there will be a delay in voltage feed compared to the rest of the components and mainboard.
 

scopus

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What kind of computer is this (model name and age).

If this is an older model, getting a secondary PSU is probably a waste of money, it's no guarantee it will work.

Even if you DO make it work (you need a proper relay for this and insight in electric circuits) the GPU may still not work because there will be a delay in voltage feed compared to the rest of the components and mainboard.

its an i5 hp 8200 elite sff, not too old myb 5-10 years
its not meant to run a full size graphics card as its small form factor but i wanted to keep the lid off and have it run a 1060. If i do this both computers will be running all the time, but if its dangerous/risky i will let the idea go. thanks
 

InvalidError

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If you simply wanted to have a secondary PSU dedicated to your old PC's GPU, having a secondary PSU would be as simple as simply connecting the two PSU's PS_ON# lines together so both PSUs turn on/off together.

Tapping into a different PC's PSU on the other hand could be problematic since the GPU may not like its VRM having AUX power but no PCIe slot power for much longer than the expected rail-to-rail rise time. If the VRM isn't fully isolating PCIe 12v and AUX 12v, there is also a chance you may end up back-feeding 12v into your other PC through the GPU and end up burning something out.
 
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Karadjgne

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Here's the other issue. It's an HP Elite 8200 sff that's not designed for a graphics card. Pretty much guarantee that the pcie x16 is power limited to 20-25w considering the 240w size and the mains power supply connector is a single 6pin, and 3x aux 4pin.

You literally cannot run a 1060 from that board, it'll physically fit, but the power delivery isn't there. That's typical and pretty common for HP low end/office class pc's.
 
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Brent73

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Hello i want to run a graphics card in an old oem computer that doesnt have a 6 pin connector. Can i use the 6 pin connector from another computer thats sitting right next to it and have both computers running at the same time?

So that older computer will be using its stock psu for all components except the 6pin which it will be getting power from an adjacent computer that will be running

I've done pretty much the same exact thing, only different ;-), with an old "office" computer. It's not the prettiest answer, but it does work. Only I didn't leave the old psu in a functional pc. I set it behind my old office pc and jumped the mobo connector so that the psu would power on. Hell in my Power Edge 2950 I run as a Home lab server, I used an old psu from one of HP's office (read, weak ass pc) computers. Was under 300 watts, so the RX580 8GB card works fine.
Do you really need the 2nd old pc to continue running while sapping off some of its 12volts? Or is it just easier for you to use that 12volts without taking out the psu?
It's best to switch on the aux psu first, then your game rig.
Mine was also in a "bookself" type case. The small form factor business machines from 10 to 15 years ago can make excellent gaming rigs with minimal effort and money invested.
Several "answers" to your inquiry are obviously not based on true knowlege, but feelings. Try not to repair or mod hardware based on feelings brother. Dig a little and find that knowledge.
 
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scopus

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thanks guys indeed getting a few interesting answers,
Here's the other issue. It's an HP Elite 8200 sff that's not designed for a graphics card. Pretty much guarantee that the pcie x16 is power limited to 20-25w considering the 240w size and the mains power supply connector is a single 6pin, and 3x aux 4pin.

You literally cannot run a 1060 from that board, it'll physically fit, but the power delivery isn't there. That's typical and pretty common for HP low end/office class pc's.

i just came across this video of a guy that got an rx560 to work in the same computer:
View: https://www.youtube.com/watch?v=MN-W-0ZIqXU&ab_channel=PhilsComputerLab


So the pci e is not power limited and can support 1060?
he used the sata to 6pin idea but read few places that using sata which uses max 54 watts should be avoided to power graphics card and is dangerous plus not many watts in the psu, im surprised he got it to run, prob better idea to connect two power supplies together like invalid error suggested
thanks
 
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