Bitcoin Forum

Greetings.

I have a 4x470 rig and when I use the PCIE2 slot for one of my risers and start mining the PC will freeze resulting in a solid color screen.

Hardware:

Intel G3260 Haswell 3.3ghz
Asrock H81 Pro BTC 2.0
G.Skill Ripjaws  DDR3 1600 8gb
EVGA SuperNova P2 1200w
Corsair 120gb SSD
ITHOO Usb3 Ver6c powered risers
4x Sapphire RX 470's

Software:

Windows 10 Pro x64
Crimson 16.2.1 + bios sign bypass / pixel patcher
MSI Afterburner (for fan profile)
Claymore's Dual GPU Miner v7.4

I do have modded bios on my cards.  They are 100% stable and I've had 0 issues with the setup as long as I don't use PCIE2.

Here is what I've tried with no luck:

- Crimson 16.2.2
- Swapped out the riser/usb cable.  
- Swapped to a different video card.
- Tried each setting under chipset > pcie2 in bios.  Auto / gen1 / gen2.
- Reinstalled chipset drivers.
- Various different windows settings.
- Flashing card back to factory rom.
- Uninstalling MSI Afterburner.
- Tried both with and without molex pcie power connectors on motherboard.

I'm out of ideas.  The card is recognized and functions properly as far as I can tell within windows.  For now I have it mining using the PCIE5 slot.  I will need that slot when the last two 470's arrive.

Check the BIOS for PCIe lane assignment settings. Some mobos need to be configured to steal lanes from the
x16 slot to enable one or more x1 slots. If not it looks like you have a bad slot on the mobo.

I checked the bios for a setting like that this morning and didn't find anything.  I will check one more time this evening to be sure.   I have another board on the way so I will swap in the new board and see what happens.

The slot that is causing trouble is the x16 slot.  All the x1 slots are functioning properly (4 out of 5 are populated). 

Thanks!

I had the same problem with an ASrock Z270 board and the second PCI-16x slot was the problem. It has produced nice Bluescreens and other errors. Replacing the board has solved my problem.

I dont no if this helps but the x16 slot is the main gpu slot is onboard graphics disabled I no some ppl where saying with it enabled they where having problems, I have one of these cards that I'm about to put together and my other rigs have and this will also have powered usb risers the question is should I run power to the motherboard molex even with poered risers  thanks

@FFI2013
Yes run power to the motherboard molex. You can test it by removing this connection than start your PC.

Thank You

I should have the last 2 cards for this rig tomorrow or Wednesday.  The H81 that was for another miner build will be here too.  Worst case I will swap the board out and RMA this one.

While I'm waiting I'm going to pull all cards.  I will plug a single card in to the x16 slot and run the miner to see if it's stable.   It's been running 24 hours using 4 x1 slots doing 122MH/s on ETH.

Ok so I guess it's fixed :D

I pulled all cards except the one I had plugged into the x16 slot (PCIE2).   -- It crashed.

I  unhooked that card and put another card into the x16 slot -- stable for 5 minutes!

I hooked the card that wouldn't work into PCIE1 (x1) along with leaving the working x16 slot card -- it works!

Now I'll hook up the other two cards and let it run overnight.


TL;DR 

For some reason my x16 slot doesn't like one of my cards.  It's not the riser/usb cable/etc.  All the cards are running identical firmware and are the same exact card.

Cheers!

There is often a problem with the power supply for the PCI-16x slot and RX480 often consumes more power than the mainboard-slot can deliver. It's a mainboard problem, I had the same problem and a reseller told me that he has seen this on many mainboards. Make a RMA for this one.

Everything is working fine after switching the card on that slot.  I can't explain why that specific card didn't work properly with that slot yet works fine in a x1 slot.

ETH - Total Speed: 183.142 Mh/s, Total Shares: 3, Rejected: 0, Time: 00:01
ETH: GPU0 30.344 Mh/s, GPU1 30.706 Mh/s, GPU2 30.364 Mh/s, GPU3 30.652 Mh/s, GPU4 30.696 Mh/s, GPU5 30.380 Mh/s

DCR - Total Speed: 2563.980 Mh/s, Total Shares: 28, Rejected: 0
DCR: GPU0 424.818 Mh/s, GPU1 429.883 Mh/s, GPU2 425.091 Mh/s, GPU3 429.127 Mh/s, GPU4 429.748 Mh/s, GPU5 425.313 Mh/s

She chooches pretty well for a 6x470 setup.  I have to work on power usage a bit.