I'm running Windows 7 x64 and have i7 3770K installed with built-in HD 4000 graphics. Intel OpenCL dlls and SDK are both installed on my system. However, for some reason only CPU is accessible via OpenCL. Intel OpenCL samples return -1 when run with -g. GPU caps viewer also shows that there is only 1 device on Intel OpenCL platform. GPU-Z shows that HD 4000 does not support OpenCL.
I also have AMD Radeon HD 7970 installed in my computer, however, the monitor is connected to the output of HD 4000 (Radeon is accessible via OpenCL even in headless mode).
Tried to disable Radeon in Windows device manager, but that does not help.
How to troubleshoot this further and/or fix it?