Rx Vegas stuck in low power mode.

[Harry O’Dell]

Hi, first post and posting this because I am clueless at what to do next

I have two Vega 64 lc edition cards. One I have from 2017 and the other recently about 6 months ago. They were running fine in a old motherboard Asus rampage from 2013 until I had an issue with the cpu not working anymore. Powered by a 1650 psu. I decided to switch to a ryzen processor so I ordered a new motherboard x470 aorus gaming 5 WiFi board. The processor is the ryzen 2600x and 32 gb of memory vulcan.

My issue now is that I am running into a problem with the vga red led on the motherboard. I have tried both cards separately and I have multiple psus I have a Corsair 1000 watt and a zalman 1250 watt. Same issue on all the power supplies with the two cards. So I was thinking ok maybe it’s the cards, I went and got my old cards vapour x sapphire cards I had lying around and I tried one of them on it’s own and it booted successfully so I don’t think it’s not the motherboard or any of those components now.

To anyone that might have any experience with it I don’t know, these cards are not easy to find now but when they turn on all I get is the gpu tach light is on green so it’s low power mode and won’t get past the vga check and this happens on both cards. At a complete loss on what to do if both cards went defective at the same time quite a rare thing to happen but you never know with electronics. I’m not too sure if they would in warranty as one is from 2 years ago essentially and the other was bought used.

I live in Ireland so it’s hard to get these checked for repairs anywhere close, if anybody’s has any solutions or possible know where I could send the cards even out of warranty for repairs it would be great to know.

Thanks

 

[LuckyBenski]

Do you have separate cables running to each GPU power connector? That's a known issue with Vega, cables with two plugs seem to cause problems with power delivery.

 

[Harry O’Dell]

Yeah, I’ve got 2 separate 8 pins connectors running to each slot. I remember having that issue when I had just the 1 card.

An interesting note if it’s any use, the zalman 8 pin connectors will give me the Radeon logo lit up red and the cube but no gpu tach it stays off. The Corsair ones will give the gpu tach low power mode but no red lights only shortly initially at start when I press the power button, and this happens on both cards. It’s a very strange issue.