First, I have tried overclocking my card with not very good results. I didn't install MSI Afterburner (as I don't have an MSI card - not that it probably matters...) but instead installed
ASUS GPU Tweak II overclocking software. (Yes, I even downloaded the ROG skinned version since I have the ROG card...) I also installed GPU-Z, which is more just a hardware monitor than anything else (which it turns out that GPU Tweak II has a built-in hardware monitor as well for the video card...). I have tried a few different overclocking settings with Genoil Ethminer (both cranking up the GPU core clock and the GDDR5 memory clock speeds as well as underclocking the GPU and overclocking the memory) and no matter what I do, I can't seem to get an average hashrate better than about 26MH/s out of my card. In fact, my card seems to get roughly the same hashrate overclocked as I get with the stock settings, which seems very odd to me.
Secondly, I recently purchased a second video card for my computer to try to mine with. I do still use my computer for many things, including gaming, and I have to close Ethminer and stop mining when I want to play games online with friends as it will kill my framerate if I mine and game at the same time. I was HOPING that with two cards, perhaps I could set it up to mine with one card and I can use the other card to play games with and have it not affect the performance of the game at all. Then, when I am at work, sleeping, or just not gaming, I can set it back to mine with both cards and get double the hashrate that I have been getting. However, this has not been the case at all and for some reason I can't get Ethminer to actually mine with both cards!
I am not sure if the problem is that I now have a mixed environment of AMD and nVidia cards in my computer or if there is some other underlying issue? I figured since I keep hearing how the AMD Radeon cards are so much better at mining Ethereum that I would try to find one. Since the AMD cards are still hard to find anywhere, I managed to buy an older used card to throw in my computer. I bought an ASUS ROG Radeon R9 380 4GB GDDR5 video card. I now have both cards in my computer (the GeForce GTX 1070 and Radeon R9 380) and I have both AMD and nVidia drivers installed. I also tried to install the
AMD OpenCL APP SDK (which I am not 100% sure if I need that to mine or not?), but the automated installer for version 3.0 doesn't work worth a damn, so I had to install version 2.9.1 instead.
However, even with all of this installed (and multiple reboots) and running Ethminer with the -G option (for OpenCL), the only card that is detected to mine with is still the GeForce 1070! That's right, even on OpenCL mining mode, it still only detects my GeForce GTX 1070 card and tries to mine with it in OpenCL mode, rather than in CUDA mode! This is very weird to me and I figured that if I ran Ethminer with the -G option, it would only use the Radeon card to mine with and I could use the nVidia card to play games with. There is also an -X option in Ethminer that will set it to mixed mode for a system with both AMD and nVidia cards in it. Even when trying that mode, it still only detects the GeForce 1070 card and mines with that. It seems like it is mining with it on BOTH OpenCL and CUDA mode though as I get status messages that it is accepting work for both OpenCL #0 and CUDA #1, but the hashrate I get is still only the same 24-26MH/s that I get from the GeForce GTX 1070 card only. I get no increased hashrate at all that would make me believe that it is actually using both cards to mine with.
Just about the ONLY way that I have managed to try to get Ethminer to use the Radeon card at all was I had to switch the monitor cable over to the Radeon card, rebooted the computer, then went into Device Manager and actually disabled the GeForce card entirely so Windows wouldn't even use it, and then started Ethminer with the -G option. However, even when doing that, Ethminer didn't seem like it identified the card properly or something. When using the GeForce card, Ethminer knows exactly what it is and says that it detected a "GeForce GTX 1070 with 8589934592 of memory". However, it doesn't properly identify the AMD Radeon R9 380 card and instead just says that it detected "Tonga". What is even weirder is that if I run Ethminer.exe -G --list-devices, it actually lists THREE OpenCL devices. OpenCL #0 is the GeForce GTX 1070. Then OpenCL #1 is Tonga with a memory size of 2147483648 and OpenCL #2 is Tonga again with a memory size of 2147483648 as well. So, for some reason, it is splitting the Radeon card into two separate video cards each with only 2GB of memory rather than a single card with 4GB of memory!! This is very bizarre to say the least! But anyways, even trying to run Ethminer with the GeForce GTX 1070 card disabled in Device Manager, it started trying to mine with the Radeon R9 380 card but shortly after it built the DAG, I kept getting 0MH/s readouts on it for about a minute and then my monitor just went totally black. It didn't go into power saving mode or anything and the monitor still detected a signal as the monitor was actually on the whole time, but it just stopped displaying anything at all. So, I had to do a hard restart on my computer and when Windows loaded up, it said that a critical error occurred with the video card and it had to be shut down.
So, for right now I am using my system backwards from how I was anticipating using it, lol... I have my monitor plugged into the Radeon R9 card and using that as my primary display card. Then, I am using Ethminer in -U CUDA Mode to mine with the GeForce GTX 1070 card only on Alpereum Pool (which BTW, as soon as I joined, they stopped doing the 0% miner fees and now have a 0.2% miner fee, but they lowered the minimum payout from 0.1 ETH to 0.05 ETH, which is fine since it takes me all week just to mine 0.05 ETH anyways with only one card getting 26MH/s...). So, at least I can still use my computer with no slowdowns using the Radeon R9 card and last night I was playing BattleField 4 with the Radeon card with no problems while mining with the GeForce GTX 1070 card. Like I said, not exactly how I had envisioned making this setup work on my system, but it is working somewhat at least. I am still pissed that I can't get BOTH video cards to mine and now I feel like I got ripped off paying a premium for another video card that I can't even mine with!
