• Discord! Come chat with us in our Discord server, open to all forum members, but now we've opened it up to all. Join our discussions by clicking the "Discord" button on the side menu!!

GPU Powering a slot powered GPU with a Pico/HDPLEX type PSU

K888D

SFF Guru
Original poster
Lazer3D
Feb 23, 2016
1,472
2,935
www.lazer3d.com
The latest generation of (low end) GPUs such as the RX 460 AND GTX 1050 are capable of decent gaming performance and a lot of the models are PCIe slot powered making them ideal for restricted power supplies.

Is it safe to power these cards using a HDPLEX or Pico type power supply? Will it cause any overloading of any kind?
 

Kmpkt

Innovation through Miniaturization
KMPKT
Feb 1, 2016
3,382
5,932
I used a slot powered GTX 950 with the Pico Box Z4 ATX 200 and eventually had a failure. The power draw from the wall was never much above 130W. I am not certain if this was a one-off, a poor quality power supply, or something else. While it was running well, I never noticed any throttling etc.
 

CC Ricers

Shrink Ray Wielder
Bronze Supporter
Nov 1, 2015
2,206
2,503
@ilovelampshade whoa, that sucks. I have a HDPLEX 160W DC-ATX and it worked well with a 90W GTX 950. I also have a 35W Intel Cpu so that helps with some overhead in power use.
 

Saltvann

Trash Compacter
Aug 26, 2016
40
11
People have been using GTX 1060 and 65W cpu with the PicoPSU and GTX 1070 and standard voltage cpu with the HDPLEX. So I would imagine that new sub 75W gpus should work well with either one of these PSU. As I understand some people have had problems with the Z4 ATX200 so the safest choice atm seems to be PicoPSU and HDplex. Unfortunately I do not have any firsthand experience just yet, but plenty of others should.
 

Kmpkt

Innovation through Miniaturization
KMPKT
Feb 1, 2016
3,382
5,932
Also worth mentioning is that HDPlex should have a Pico solution for 19V available shortly.
 

K888D

SFF Guru
Original poster
Lazer3D
Feb 23, 2016
1,472
2,935
www.lazer3d.com
People have been using GTX 1060 and 65W cpu with the PicoPSU and GTX 1070 and standard voltage cpu with the HDPLEX.
I was meaning specifically for GPUs that draw 100% of their power through the motherboard. Does this put stress on the main rail?
The GTX 1060 and 1070 require separate power connectors, the system overall needs more power, but I would imagine that there is less power going through each cable if that makes sense?
 

Aibohphobia

Jessica. Wayward SFF.n Founder
Gold Supporter
Feb 22, 2015
4,962
4,757
It shouldn't be any different than a normal video card that draws 60-75W from the slot and the remainder from the 6-pin/8-pin connectors.
 

iFreilicht

FlexATX Authority
Feb 28, 2015
3,243
2,357
freilite.com
It shouldn't be any different than a normal video card that draws 60-75W from the slot and the remainder from the 6-pin/8-pin connectors.

The thing is that spikes in power draw that go above the allowed maximum can't be supported through the 6pin connector, just through the slot itself. And the mainboard only gets 12V through 2 pins, so the concern is at least somewhat justified.
 

Aibohphobia

Jessica. Wayward SFF.n Founder
Gold Supporter
Feb 22, 2015
4,962
4,757
During the whole RX 480 power draw fiasco, the motherboard makers said that a quality board can easily handle momentary power spikes through the slot, it's the sustained above-spec power draw that made the 480 such a problem at launch.
 

K888D

SFF Guru
Original poster
Lazer3D
Feb 23, 2016
1,472
2,935
www.lazer3d.com
I wasn't sure if the GPU drew primarily through its PEG connector, and therefore sharing the overall system load between the 24pin ATX connector and PCIe power connector. But I think my question has been answered above, most cards will draw up to the 75W through the slot and gets topped up by the PEG connector.

So therefore a 70W GPU and 60W CPU should easily be powered by 150W Pico style PSU?
 

Aibohphobia

Jessica. Wayward SFF.n Founder
Gold Supporter
Feb 22, 2015
4,962
4,757
o therefore a 70W GPU and 60W CPU should easily be powered by 150W Pico style PSU?

I believe the 12V 160W PicoPSU that is commonly used is safely capable of a fair bit more wattage provided the power brick is up to the task and there is adequate cooling so that should be fine.
 
  • Like
Reactions: CXH4 and Phuncz