Question Can I power my GPU through a secondary PSU?

[XerneraC]

I have an HP Proliant DL380 G7 server, in which I want to install an RX 580 to build a render server.
I saw that with a riser, you can use PCI-E cards up to 150 Watts. Sadly, the 580 is rated at a TDP of 185 Watts.

Can I use a secondary PSU to power the 580?
I know that the proper thing to do is to get a different server, but I have this server, and I'm okay with a solution being somewhat improper.

 

[jojesa]

Only if you could power on and power off both PSUs at the same time and both PSU share common ground wire.

Since the HP might have a proprietary PSU that could be a recipe for disaster.

 

[USAFRet]

Can you?
Maybe.

Should you?
No.


sniff sniff....I smell smoke.

 

[XerneraC]

Through googling, I found, that there are little boards that synchronize multiple PSUs. They are intended for mining rigs, but shouldn't they technically also work in my case?

 

[jojesa]

Through googling, I found, that there are little boards that synchronize multiple PSUs. They are intended for mining rigs, but shouldn't they technically also work in my case?

If you have looked closely, those are standard PSUs that conform to the ATX specifications.

They could work if you had two or more standard PSUs with standard specs, such as ATX specification.
As far as I know the HP Proliant servers use proprietary PSUs that do not conform with ATX specs.

 

[DSzymborski]

It's also a little awkward to do a GPU on a separate PSU because you're in the weird situation of the GPU essentially being powered from two PSUs (since a lot of the power will come from the PCIE slot). It's really not ideal unless you absolutely have to. I'd personally search for a different solution. If you could still grab an RX 580 for $150 new, then sure, maybe, but today? Meh.

 

[XerneraC]

If you have looked closely, those are standard PSUs that conform to the ATX specifications.

They could work if you had two or more standard PSUs with standard specs, such as ATX specification.
As far as I know the HP Proliant servers use proprietary PSUs that do not conform with ATX specs.

Most I saw used something like a SATA or a Molex cable to sync the PSUs. I think I could probably get one of them from my server. But I'd probably have to make a common ground myself.

 

[XerneraC]

It's also a little awkward to do a GPU on a separate PSU because you're in the weird situation of the GPU essentially being powered from two PSUs (since a lot of the power will come from the PCIE slot). It's really not ideal unless you absolutely have to. I'd personally search for a different solution. If you could still grab an RX 580 for $150 new, then sure, maybe, but today? Meh.

I already have both the server and the 580

• The 580 was my old graphics card from my rig before I upgraded
• The Server: I originally bought as a file server, but I never set that one up

Both of them don't really find any use right now, so I thought of putting them together.

Maybe I can use a riser that needs separate power and run it entirely off the secondary PSU?

 

[USAFRet]

Most I saw used something like a SATA or a Molex cable to sync the PSUs.

No, it wasn't SATA or Molex.

If you found some video that did exactly what you want, with the exact same parts....then do exactly what that guy said.
But you've not found that exact same thing, right?

 

[XerneraC]

No, it wasn't SATA or Molex.

If you found some video that did exactly what you want, with the exact same parts....then do exactly what that guy said.
But you've not found that exact same thing, right?

I have not found that video. Do you have a link or something?

 

[USAFRet]

I have not found that video. Do you have a link or something?

What were you referring to with - "Most I saw used something like a SATA or a Molex cable to sync the PSUs " ?

What and where did you see?

 

[XerneraC]

What were you referring to with - "Most I saw used something like a SATA or a Molex cable to sync the PSUs " ?

What and where did you see?

(https://www.amazon.com/Add2PSU-Multiple-Adapter-Starter-Extender/dp/B077RGRTSG)
Something along the lines of this. Given, it does look pretty sketchy. From my understanding it monitors the SATA power cable for any changes on the main PSU, and uses the relay (as to completely separate the two circuits I presume) to shorten the pins on the 24-Pin to mirror the change over to the auxiliary power supply.
I've seen similar boards that use a Molex connector instead of a SATA power connector.

 

[USAFRet]

Something along the lines of this.

Again....sniff sniff....

 

[XerneraC]

Again....sniff sniff....

I mean, it doesn't look to be such a complicated device, and it should probably eliminate the syncing issue entirely.

 

[USAFRet]

I mean, it doesn't look to be such a complicated device, and it should probably eliminate the syncing issue entirely.

No, it does not look like a complicated device.

The question is...does it work?
Power supplies are the heart of the system. Do it wrong, and things can go very bad, very quickly.

 

[USAFRet]

Further, disregarding the power and GPU...what CPU and RAM are involved?
Are those applicable to this render server?

 

[jojesa]

I mean, it doesn't look to be such a complicated device, and it should probably eliminate the syncing issue entirely.

It is very simple, straight forward and not complicated at all... when you use standard ATX PSUs.

Have you looked at the ProLiant PSU?
Does it have a 24-pin ATX connector?

 

[NightHawkRMX]

What about just buying an RX480. Its nearly the same card but with a tdp of 150w.

Does this PSU have a 6 or 8 pin pcie connectors though?

 

[Jacob 51]

It's not recommended. I'd advise to buy a GTX 1660 Ti. It's kinda the same performance and is rated at 120 Watts.

 

[XerneraC]

Further, disregarding the power and GPU...what CPU and RAM are involved?
Are those applicable to this render server?

It has 2 E5645 CPUs and 56 GB of RAM. This is what I can tell you right now, I could give more useful information when I'm back home.

I don't necessarily plan on using them to render, but I wouldn't want a situation where I could run into power issues when they do start to be used.

 

[XerneraC]

It is very simple, straight forward and not complicated at all... when you use standard ATX PSUs.

Have you looked at the ProLiant PSU?
Does it have a 24-pin ATX connector?

The PSU is not standard, it connects directly to the motherboard through one big fat connector. The sync boards I found only seem to need a 24-Pin on the auxiliary PSU though. And common ground I could get from the PCIE power connector, which the server does offer.

 

[XerneraC]

What about just buying an RX480. Its nearly the same card but with a tdp of 150w.

Does this PSU have a 6 or 8 pin pcie connectors though?

I'm looking to do this with the components I mentioned because I already have them, and I'm searching for a way to use them as opposed to let them collect dust.

The server offers a 10-Pin cable intended for expansion cards that can be adapted to an 8-Pin PCIE power connector through an official adapter.

 

[XerneraC]

I also found these:

Again, intended for mining, but they might work. They probably help separate the two power circuits. (with some considerable PCIE bandwidth loss, but that is acceptable, since once the scene is sent over to the GPU it can just render on its own.)

 

[--SID--]

I also found these:

Again, intended for mining, but they might work. They probably help separate the two power circuits. (with some considerable PCIE bandwidth loss, but that is acceptable, since once the scene is sent over to the GPU it can just render on its own.)

I've seen a lot of melted sata cables that way. 75w through one tiny 12v wire .... nope, don't do it.

 

[XerneraC]

I've seen a lot of melted sata cables that way. 75w through one tiny 12v wire .... nope, don't do it.

Are you talking about the SATA power cable? Because if so, you can remove that from the board and stick a 6-Pin PCIE directly into it, which should handle 75 watts perfectly fine.