Some GTX 1060 3GB cards have low hashrate with Ethash coins.

Ethash algorithm behaves a bit strange on my mining rig with HiveOS and 8 GTX 1060 3GB. Four MSI ARMOR cards with Sumsung memory (OC +1500 mem) have 24+ MH/s, two other cards (OC +600 mem) have 21+ MH/s and two other slow MSI cards (also OC +600 mem) have only 18+ MH/s. I tried to switch risers, PSU, PCI slots and move the cards across rigs, but with no success.

Today I did a pure experiment. I plugged one of the slow cards to a Windows 10 machine with 1000W PSU directly via PCI slot without riser, started Claymore Miner with Musicoin (that has a lower dag size than Ethereum) and got the same result as before, without OC the card had 15+ MH/s (normally it should be 19+ MH/s):


Molten SATA power connector on a mining rig.

I have a mining rig with 8 GTX 1060 3GB connected via risers, the risers are connected via SATA power connectors to Corsair HX850. When the rig stopped working I noticed that one SATA connector on the PSU is molten:


How I built QT 5.11.1 for Android on Windows

I tried to build QT 5.11.1 for Android on Windows, and “configure.bat” completed successfully, but “mingw32-make” failed with with the following error:

No rule to make target 'vulkan/qvulkanfunctions_p.h', needed by '.obj\qvulkaninstance.obj'.

It is the bug fixed in QT 5.11.2 that is planned on August/September 2018.

When I build the master branch and copied the following files from it to \qtbase\src\gui\vulkan manually:


and started “mingw32-make” again I got another error:


Mining Ethereum on Ubuntu 18.04 with GeForce GTX 1060 3GB

I am not a Linux expert, so it took me some time to configure my mining rig on Ubuntu 18.04 with NVIDIA GeForce GTX 1060 3GB, and I wrote down all the steps I did:

First I installed NVIDIA driver, but OpenCL did not install automatically with it and I installed it manually with the following command:

sudo apt install -y ocl-icd-libopencl1

Then I installed CURL:

sudo apt install -y libcurl3

not ‘curl’ and not ‘libcurl4’ packages, otherwise the miner will fail to start reporting the following error message:

./ethdcrminer64: /usr/lib/x86_64-linux-gnu/ version `CURL_OPENSSL_3' not found (required by ./ethdcrminer64)


PHP script that saves client IP address to a file.

Below I wrote down a simple PHP script that saves client IP address to a file. If the IP address of your home machine periodically changes, you can store it on a web server once a minute by scheduling a task like this:

sudo crontab -u <user> -e
* * * * * wget -q -O /dev/null -o /dev/null ""

where ip.php is the following PHP script:

How I compiled OpenSSL from sources with VS2015

I installed Perl, downloaded and extracted OpenSSL 1.1.0h and built 64 bit version in VS2015 x64 Native Tools Command Prompt with the following commands:

set PATH=%PATH%;C:\Perl64\bin
perl Configure VC-WIN64A no-asm

32 bit version can be built with VC-WIN32 configuration option as described in INSTALL:

on Windows (only pick one of the targets for configuration):
    $ perl Configure { VC-WIN32 | VC-WIN64A | VC-WIN64I | VC-CE }
    $ nmake
    $ nmake test
    $ nmake install

probably ‘A’ suffix means AMD and ‘I’ means something else, so we need ‘A’.


Multiple versions of Microsoft.Web.Administration.dll in IIS 10

On some Windows 10 machine with IIS 10 installed I have three Microsoft.Web.Administration.dll:

Two versions and in GAC (C:\Windows\assembly\GAC_MSIL\Microsoft.Web.Administration\) in and folders respectively and one version in C:\Windows\System32\inetsrv\.

The following XML element in a Visual Studio project file adds a reference to version of Microsoft.Web.Administration.dll:

<Reference Include="Microsoft.Web.Administration, Version=, Culture=neutral, PublicKeyToken=31bf3856ad364e35, processorArchitecture=MSIL">

The same XML element with SpecificVersion=False will automatically reference the highest available version on this machine that is


Regular expressions for editing DEF-file (Windows Module-Definition file)

The following regular expression (find/replace pair) in Visual Studio format removes extra whitespace and @ symbol from a DEF-file:

^[ \t]+(\b(?<name>_\w+|[\w-[0-9_]]\w*)\b)[ \t]+@(?<index>\d+)(?=\r?$)

and converts it to such a form when it can be imported to MS Excel and sorted by the function number, so you can manually add new functions by incrementing the last number.

To convert the file back the following find/replace pair can be used:

^(\b(?<name>_\w+|[\w-[0-9_]]\w*)\b)[ \t](?<index>\d+)(?=\r?$)

Setting up QT Creator 4.6.1 for Android development on Windows 10

First I installed Android Studio. When it started I set an option to create the application with Native C++ support and Android NDK was automatically installed to C:\Users\AppData\Local\Android\Sdk\ndk-bundle, also I added Android-19 API level and somehow CMake was installed to C:\Users\AppData\Local\Android\Sdk\cmake\3.6.4111459. Then in QT Creator I opened Tools->Options->Devices->Android and specified the following paths:


Building QT 5.10.1 from sources with VS2017

I am not sure it is a correct way, but I was able to do this:

git clone --recursive --branch v5.10.1

and all the submodules were checked out with commit hashes tag v5.10.1 points to:

You are in 'detached HEAD' state. You can look around, make experimental
changes and commit them, and you can discard any commits you make in this
state without impacting any branches by performing another checkout.
Submodule path 'qt3d': checked out '31f424bb81cd2583920d3d521e1e01f01c2d28e2'