Vega 56 only working with crappy PSU

[Kevi983]

Hello users of the LTT forum,

 

after a lot of reseating and troubleshooting I finally decided to try another PSU since my vega wasn't giving me a display signal.

 

I replaced my immaculate Straight Power 10 600 Watt Gold Efficiency PSU, which has been powering a much more power hungry GPU for about a year now, with a 450W System power 7. 

 

And this hail mary worked for some reason.

 

I'm sort of confused and also pissed since I wasted so much time on troubleshooting and cannot fathom why the vega only accepts my crappy 10 year old PSU.

 

I'm also not entirely sure whether I can now be certain that the GPU is fine since I've been planning to sell it if I got it to work.

 

Any input is appreciated, the card has been running Doom Eternal/Forza Horizon in 4k without issues for multiple hours now.

 

Pictured below: the GPU in question and the AMD Software while Doom is running.

 

Greetings from Germany, Kevin

 

 

 

 

[Zando_]

Vega cards are known for massive transient spikes (giant wattage spikes for a couple milliseconds). Your nice unit probably isn't set up to account for these if it's an older design, so it trips OCP/OPP and shuts off the PSU. Lots of good units had this issue when the Vega cards released, no mark against their quality just the OCP/OPP settings had to be updated, and have been on all the newer refreshes. The crappy unit likely does not care and is just allowing the GPU to do whatever it wants. 

[Kevi983]

11 minutes ago, Zando_ said:

Vega cards are known for massive transient spikes (giant wattage spikes for a couple milliseconds). Your nice unit probably isn't set up to account for these if it's an older design, so it trips OCP/OPP and shuts off the PSU. Lots of good units had this issue when the Vega cards released, no mark against their quality just the OCP/OPP settings had to be updated, and have been on all the newer refreshes. The crappy unit likely does not care and is just allowing the GPU to do whatever it wants. 

Makes a lot of sense, thanks!

[Mark Kaine]

had similar issues with a straight power 10... they're trash .

 

(my much cheaper pure power works lol)

[Queen Chrysalis]

Not to be rude, but you should have sold that Vega in 2021.  I had a dual vega 64 setup until then and I got $800 a pop for them from someone doing machine learning.  You could have gotten a 6600 on release for like $400 and that would have been significantly faster at less than half the power.

 

In relation to now, yeah those things are total braphogs on power.  You may still be able to sell the GPU to a hackintosher and get like a 1070 or something for   less that won't need nearly as much power and will probably game the same or slightly better.  You might even be able to swing a used 6600 or 5700xt that will be notably faster.