problems recognizing 2nd video card

Are both cards showing in Device Manager and Nvidia Control Panel ? Check the sli bridge is seated correctly, although that doesn't effect the card showing, and check that sli is enabled in Nvidia Control Panel.

Plug monitor into each card to see if they re working, with sli bridge on and off.


Edited by bprat22 - 13 May 2016 at 2:18am

I understood that.      Just trying to gather info from different sources in case of faulty info from Bios, which isn't likely but ya never know.

I'd swap the cards, putting # 2 in the first slot, etc and see if the card is recognized in the top slot.  Could be a bad card.  If its seen in top slot and the other card is now not seen in 2nd slot, then could be a mobo issue or Bios.   The cards should auto recognize and setup correctly, but is there an adjustment in the Tools menu to select the slots for x8x8 or x16x8? 

Not that I'm aware of.   So many different boards and bios's can't really say for certain.   You are right, it should be an auto setup with 2 cards. 

Swapping the cards tonight might help determine a bad card or a mobo issue.  

Plugging the monitor into each card separately will also give an idea if both cards are actually working, regardless of the lights displayed.  

I have seen installing/reinstalling  new drivers using the Clean install fix some oddball issues.   That is a Windows tool and shouldn't effect Bios but  never say never.

A call to DS might be needed if none of my suggestions or your efforts work out.

 

The power cables for the GPU's look secure on the PSU end, but I haven't actually tried to reseat them. The space is pretty tight, and I think I'd have to unplug everything to get to the GPU power cables.

I forgot to mention, this is a 1000 W PSU, so raw power availability isnt the issue either.

No cable sleeves.

I do have an SSD, but I dont think its physically near the card. I just had to look up m.2 on wikipedia, so now we're really getting into unfamiliar territory for me :-)

I removed both cards just now. Put #2 in the #1 slot. Computer booted just fine. Device manager recognized card in slot 1. So its not the card. Put card #1 in the #2 slot. It wasn't recognized.

So its either the mobo, or something power cable related (the cards were swapped, but the power cabling wasn't.)

Or...something I haven't considered.

The mobo definitely supports 2 video cards (it says as much inside the BIOS). I don't have the SLI bridge connected at the moment.

I've gone over the BIOS settings again and again, and there's nothing that stands out for enabling the 2nd slot. The manual really seems to imply its automatic detection.

Originally posted by bprat22 The Asus Maximis 8 Hero is sli capable and doesn't have the Pcie lane switches to disable slots. My guess is a bad Pcie slot if they both work in #1 slot but neither work in #2 slot, if that's the case. I would swap the power cables between cards just to make sure. Doubt it's that but gotta cover everything.

If both cards, show up individually when you swap position from whatever PCI slot you have the second card in, into the first one. That's a fairly clear indication that we're having a motherboard problem. In fact to help eliminate the Power Supply, you don't even have to swap cables. Simply take the cables plugged into which card isn't showing up and plug them into the first card and vice versa. But I highly doubt this is a power supply/cabling issue, especially if both cards "light up" white on the power ports and not red.

I'm assuming you're using GPU post within the bios to help identify which cards are showing and at what speed. I'd also have to read the documentation, but I see no reason why it would auto downclock the speed from x16 to x8 to match the other one, as I've seen plenty of sytems where the primary card still runs at 16 and not 8... unless there are three cards or a demand for the lanes to be shared because of more hardware plugged in.

We digress, simply swap out the cards with each other, boot up and check GPU post. If you still only see the one card (in the top spot not in a new spot obviously) on GPU post, you only have a few options.

Contact DS to send it in and get fixed, contact ASUS for troubleshooting and possibly RMA of the motherboard, or RMA the graphics card(s). I'd bet a months wage that it's either the card or mobo... nothing else.