I compiled a quite large C++ project in Visual Studio 2010 Ultimate using the Intel Composer compiler 2011, DirectX SDK (June 2010) and Intel TBB. After starting (either the Release or Debug assembly) directly from within Visual studio in debug mode (by pressing F5) the project runs much faster than when it started the outside of Visual studio (starting the .exe file directly).

Application type - event simulation of molecular dynamics. In general, even visually, i can see how the motion of particles (about 100 000 molecules) is much slower when you run the exe-file directly. Priority class for the application process is HIGH_PRIORITY_CLASS, work-threads of applications (responsible for the processing of events) have priority THREAD_PRIORITY_HIGHEST. As a result, when the application runs from the visual-studio (via F5) work threads are faster than running via Ctrl+F5 or exe-file directly

What could cause this and how can it be fixed?

C++ compiler is configured for X86:

Platform: Win32
Target machine: MachineX86 (/MACHINE:X86)

My PC:

Processor - Mobile DualCore AMD Turion X2 Ultra ZM-80, 2100 MHz (5.25 x 400)
Video - ATI Mobility Radeon HD 3650 (M86) 512MB
OS - Windows 7 Ultimate 64-bit

P.S. I'm sorry for my English - I'm from Russia