From 9804d2d6a1b762e61e20168933626989ec730cef Mon Sep 17 00:00:00 2001 From: Con Kolivas Date: Fri, 5 Apr 2013 10:19:28 +1100 Subject: [PATCH] Add extensive GPU FAQs for the flood of new Scrypt miners. --- README | 75 ++++++++++++++++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 71 insertions(+), 4 deletions(-) diff --git a/README b/README index 88d6bd2c..74511b1b 100644 --- a/README +++ b/README @@ -890,9 +890,9 @@ need to set is the Intensity. Q: What happened to CPU mining? A: Being increasingly irrelevant for most users, and a maintenance issue, it is -no longer under active development and will not be supported unless someone -steps up to help maintain it. No binary builds supporting CPU mining will be -released but CPU mining can be built into cgminer when it is compiled. +no longer under active development and will not be supported. No binary builds +supporting CPU mining will be released. Virtually all remaining users of CPU +mining are as back ends for illegal botnets. Q: I upgraded cgminer version and my hashrate suddenly dropped! A: No, you upgraded your SDK version unwittingly between upgrades of cgminer @@ -910,7 +910,8 @@ this time unless you are using an ATI 7xxx card that needs it. Q: Which ATI SDK is the best for cgminer? A: At the moment, versions 2.4 and 2.5 work the best for R5xxx and R6xxx GPUS. -If you are need to use the 2.6+ SDK ofr R7xxx or later, the phatk kernel will +SDK 2.6 or 2.7 works best for R7xxx. SDK 2.8 is known to have many problems. +If you are need to use the 2.6+ SDK or R7xxx or later, the phatk kernel will perform poorly, while the diablo or my custom modified poclbm kernel are optimised for it. @@ -931,6 +932,69 @@ Q: cgminer reports no devices or only one device on startup on Linux although I have multiple devices and drivers+SDK installed properly? A: Try "export DISPLAY=:0" before running cgminer. +Q: cgminer crashes immediately on startup. +A: One of the common reasons for this is that you have mixed files on your +machine for the driver or SDK. Windows has a nasty history of not cleanly +uninstalling files so you may have to use third party tools like driversweeper +to remove old versions. The other common reason for this is windows +antivirus software is disabling one of the DLLs from working. If cgminer +starts with the -T option but never starts without it, this is a sure fire +sign you have this problem and will have to disable your antivirus or make +exceptions. + +Q: Why don't you provide win64 builds? +A: Win32 builds work everywhere and there is precisely zero advantage to a +64 bit build on windows. + +Q: Is it faster to mine on windows or linux? +A: It makes no difference. It comes down to choice of operating system for +their various features. Linux offers much better long term stability and +remote monitoring and security, while windows offers you overclocking tools +that can achieve much more than cgminer can do on linux. + +Q: Cgminer cannot see any of my GPUs even though I have configured them all +to be enabled and installed OpenCL (+/- Xorg is running and the DISPLAY +variable is exported on linux)? +A: Check the output of 'cgminer -n', it will list what OpenCL devices your +installed SDK recognises. If it lists none, you have a problem with your +version or installation of the SDK. + +Q: Cgminer is mining on the wrong GPU, I want it on the AMD but it's mining +on my on board GPU? +A: Make sure the AMD OpenCL SDK is installed, check the output of 'cgminer -n' +and use the appropriate parameter with --gpu-platform. + +Q: I'm getting much lower hashrates than I should be for my GPU? +A: Look at your driver/SDK combination and disable power saving options for +your GPU. Specifically look to disable ULPS. + +Q: Can I mine with AMD while running Nvidia or Intel GPUs at the same time? +A: If you can install both drivers successfully (easier on windows) then +yes, using the --gpu-platform option. + +Q: Can I mine with Nvidia or Intel GPUs? +A: Yes but their hashrate is very poor and likely you'll be using much more +energy than you'll be earning in coins. + +Q: Can I mine on Linux without running Xorg? +A: With Nvidia you can, but with AMD you cannot. + +Q: I'm trying to mine litecoin but cgminer shows MH values instead of kH and +submits no shares? +A: Add the --scrypt parameter. + +Q: I can't get anywhere near enough hashrate for scrypt compared to other +people? +A: You may not have enough system RAM as this is also required. + +Q: My scrypt hashrate is high but the pool reports only a tiny proportion of +my hashrate? +A: You are generating garbage hashes due to your choice of settings. Your +Work Utility (WU) value will confirm you are not generating garbage. You +should be getting about .9WU per kHash. If not, then try decreasing your +intensity, do not increase the number of gpu-threads, and consider adding +system RAM to match your GPU ram. + Q: My network gets slower and slower and then dies for a minute? A; Try the --net-delay option. @@ -978,6 +1042,9 @@ To permanently give your account the 'dialout' group: sudo usermod -G dialout -a `whoami` Then logout and back in again +Q: Can I mine scrypt with FPGAs or ASICs? +A: No. + Q: What is stratum and how do I use it? A: Stratum is a protocol designed for pooled mining in such a way as to minimise the amount of network communications, yet scale to hardware of any