Here is my 4GH [scrypt] Rig, with 6x HIS 7950 IcqQ x2 @666 khash/s - update: 673
This was fun to build while waiting way too long for my grakas
(actual hashrate value in cgwather and shares accepted count in cgminer are buggy)
The current setup is:
6x HIS 7950 IceQ X2
LEPA 1600W NT
4GB G-Skill Ripjaws
40 GB Seagate HDD
current Riser: 3*powered x1, 1*non powered x1, 1*x16 riser@2nd Slot(always counted from Top)
Rig consumes 1490W now.
-skipped using 4th Slot.
-used shortening mod on 5th Slot.
-flashed Bios with 1003,firstname.lastname@example.org VDDC
-used optimized kernel binary from https://forum.litecoin.net/index.php/topic,6058.75.html
-used 13.1 Driver from techpowerup, installed it without sdk and manually installed amd app sdk(dont know which version is installed right now)-
-currently running under Windows8 64 bit with cgwatcher and cgminer3.5 with param:
CoreClock: 1092 Mhz
MemClock: 1490 Mhz
ThreadConcurrency=22400 Intensity=19 GpuThreads=1 Vectors=1 Worksize=256
My old config was 21712TC with 1003(Core)x1490(Mem)@1.087V - By increasing core hashrate fall down - I stucked at 599kh/s.
Each card consumed 208W
With the new kernel binary and TC switch to 22.4k, it increased to 616Kh/s (2.75%)
..and it had also brilliant secondary effect:
Now i`m able to increase core frequency almost linear to my hashrate. I stopped with 1092Mhz with 666Mhz and...
FINALLY GOT MY 4 GH/s !!!!
Each card now consumes 224W so I think i have to do some more undervolting again
Did a lot fine tuning and ended with:
+ pushed core to 1104 on 5 cards => + 7 Kh/s each
+ decreased vddc to 1.081V => - 2.5 W each
+ switched TC to 24k => + 2 KH/s each
just love the result plus ~47 Kh/s, for 12.5W less power !
pictures get updated, when it pass the long term stability test
With my second rig I had some stability issues. The reason for that had been those fucking default energy-saving options of windows.
- Switch to your energy profile menu and select advanced settings. Disable energy saving for PCI Express
Scrypt mining just sends a few instructions & results over PCI Express, so this could be missinterpreted as a low bus usage.
when you want to rebuild this, you first have toundervolt the graphicards bios before
mining, cause you would exceed the PSU limits!
gpu mining is just a wonderful hobby
hope u enjoy it and could probably find anything to incease your hashrate too
thank you. your post inspired me to build my own version of your creation. i had to make it more compact and incorporate 3 750w psus. i think you've made the best 6gpu rig composition...