Low Hashrate VEGA 56/64

[carlosmonaco]

Hello,
I'm experiencing some troubles on my Vega RIGs. I have on the first one 2 Vega 64 and 6 Vega 56 with Vega 64 bios. I have exactly the same setting on all the card but some card are running around 2Kh/s and some around 1,7Kh/s or below .
This is the result on XMR Stak with 1932 intensity on both thread:

HASHRATE REPORT - AMD
| ID | 10s |  60s |  15m | ID | 10s |  60s |  15m |
|  0 | 877.0 | 871.0 | 871.4 |  1 | 865.2 | 869.9 | 871.3 |
|  2 | 875.2 | 879.9 | 877.6 |  3 | 872.9 | 874.5 | 877.5 |
|  4 | 954.7 | 958.7 | 960.9 |  5 | 961.6 | 962.3 | 960.7 |
|  6 | 985.8 | 985.7 | 987.6 |  7 | 985.5 | 987.5 | 987.9 |
|  8 | 986.1 | 987.1 | 986.4 |  9 | 987.1 | 988.0 | 986.5 |
| 10 | 955.7 | 960.8 | 961.7 | 11 | 964.3 | 961.1 | 961.8 |
| 12 | 948.7 | 961.6 | 963.0 | 13 | 970.6 | 963.0 | 962.7 |
| 14 | 874.1 | 878.2 | 876.6 | 15 | 881.4 | 877.7 | 876.5 |
-----------------------------------------------------
Totals:   14978.6 14998.3 15012.8 H/s
Highest:  15070.8 H/s

I'm using XMR Stak with 1932 intensity on both thread but I tried 2016/1800, 2016/1600, the results are almost the same, some are running lower than others. ( I also tried cast XMR but I also get this king of results)

This is my setup:
Asrock h110 BTC Pro
16 GB of ram
Intel G3930
Risers Yikeshu
GPU : 2 RX Vega 64 and 6 Vega 56 ( both Sapphire )
256 Go SSD
Power supply : Corsair HX1000 *2

I'm Using a Windows 10 UNA 64 bit 2016 LSTB but I also tried Windows 10 1709 but nothing better.
I set virtual memory to 1024*16*8 Cards

I'm using softpower play from here :https://www.youtube.com/watch?v=AXMbVfqsVi4

With overdrive and tool I'm using 1395/1090 ( CORE/MEM) at 870/850. I was using before 1408/1100 at 925/905 but results were almost the same with more power consumption.

I really don't know how to improve stability and speed on those cards and I really need your help!
Can it be the CPU? the risers ? the motherboard ?

[1715525331]

1715525331

[1715525331]

1715525331

[1715525331]

1715525331

[carlosmonaco]

No one ?

[POM]

What driver are you running, blockchain beta? Adrenalin?

[Deadstock]

Make sure HBCC Memory Segment is turned on for all Vs and try the Blockchain Aug 23rd release drivers. you should be able to get 2k h/s easily.

[cod3gen]

Utility like GPU-Z active? Or any similiar gpu monitoring software, thats enough to lower your hashrate. I also have this from time to time, but usually just restart miner one time and it runs stable 2k/h 24/7. However if i start GPU-Z hashrate goes down to 1.6-1.7 K/h immediately. Im using AMD XMR Miner.

[Goldenbunip]

My money is on your HBM temperatures being your issue.

If HBM gets above 55C your performance gets hammered. I'm running in CAST with 1300soc timings on two different rigs, as my vegas just would not play nicely together (one card just will not work in any system with any other card in it!!)

I can see on the weaker water cooled rig that if the HBM/Core gets to 55C the performance drops from +2000hs to 17/1800 area. 

Do you know what temps your running? Are the higher performance cards cooler by some chance?

Also well done on getting all cards at over 1100 memory timings.

[carlosmonaco]

thanks for the answer , it's not the temperature , even at the begining at low temperature some are running faster than others. I tried 4000 rpm but same results. Im using blockchain drivers (23 august). And I'm not using GPU Z or anything. I'm using a custom windows on windows 10 LSTB but I tried with fall creator update with same results

[Shnikes101]

If you can identify the cards that are the problem, try dropping intensity to 1800/1800. You can also try turning the volts back up on those problem cards - 905. If they are 56's you could flash those back to stock and run them with pp tables and your settings and get 1800 - 1900 h/s. Are you running a dummy plug or display off igpu? Could explain one card.

Contrary to what someone else said, I run with HBCC turned off on Blockchain drivers.

8 Vegas on a board is impressive. People have run into lots of headaches as you add more cards.
Personally I run my rigs at 4 Vegas each but that is mainly due to the age of my rigs and at the time we hadn't figured out how to get more than 4 running. That said, I don't have hashrate problems.

[carlosmonaco]

I Have Two RIG with 8 VEGA and one with 5 , all have the same unexpected results . I tried 64 bios, stock bios , turning the volts back up . I will try to lower intensity on those cards tonight. I hhad a lot of headaches to stabilize It.

8 cards RIG are running around 15000h/s but only few cards are running above 2Kh/S

[tb051004]

Did you try the windows 1703 ? Because the blockchain driver is for windows 1703.