Hi everyone!

After fiddling with sgminer 5.5.5 for a few weeks now, going through numerous crashed, restarts and bluescreens, i finally found the optimal 4GB card configuration that works like a charm, so i figured i'd share my config.

Current uptime: 2 days, 6 hours, 46 minutes. Mining on nanopool with <4% reject rate!

If you like it, please feel free to donate a few beers

ETH: 0x857B8196359305579586e2e510986d416bf87e23
ETN: etnkHvi86rUVLso1rKCGB6A95Apvbp7htDJEHfLAk31iSTrZoehXKuBhPnCo2hB6aeUaeq8AwnpMKbX vPN8Bwjy381SsH7toge

I have a 12 gpu rig with a combination of 4GB MSI Gaming X and Sapphire Nitro + cards with Elpida, Samsung and Hynix memory.

Currently i am mining at 10.050Kh/s or on average 837.5 h/s per card, roughly 20% higher than the 700 hash rate average shown on whattomine.com. My best card gets 911 h/s, worst gets 779 h/s.

All cards are bios modded undervolted to 900-950mV, running 1900-2100 memory speed with 1150 gpu clock. GPU voltage underclocked by 3-4 clicks (i.e. 65288 standard tuned down to 65284-5).

Total power usage: 1125W
Memory errors: <50/day for 2 cards (still tuning these a bit), 0 for rest of cards

The key here are the following three items:
rawintensity: 896
worksize: 7
gpu-threads: 2

Raw intensity is defined as #computing units * worksize * 4 (32 * 7 * 4 = 896)
Worksize directly affects the memory used on the card. Most people use 8 (and i used to as well), but memory gets to full it starts giving errors. 7 is the optimal number (3614MB Memory used). 8 is too much and you WILL get blue screens and crashes.
Gpu threads - # of processing threads. Using 2 gives roughly 10-20% higher hashes than 1 as long as your memory is not maxed out.

Config as follows:

Code:

{
   "pools":
   [
   {
   "name": "yourpool",
   "url": "yourpooladdress:port",
   "user": "youruser",
   "pass": "yourpass (default x)",
   "priority": "0",
   "profile": "xmr"
   }
   ],
   "profiles":
   [
   {
   "name": "xmr",
   "algorithm": "cryptonight",
   "rawintensity": "896",
   "worksize": "7",
   "gpu-threads": "2"
   }
   ],
   "default-profile": "xmr",
   "no-extranonce": true,
   "gpu-platform": "1"
}

If you have any questions i'll be happy to answer them

Any comments are welcome as well!

If you found this useful, please buy me a couple beers!

ETH: 0x857B8196359305579586e2e510986d416bf87e23
ETN: etnkHvi86rUVLso1rKCGB6A95Apvbp7htDJEHfLAk31iSTrZoehXKuBhPnCo2hB6aeUaeq8AwnpMKbX vPN8Bwjy381SsH7toge