Here is just small piece of assembler code to determine CPU frequency in MHz.
function CPUSpeed: Double;
const DelayTime = 500;
var
TimerHi, TimerLo: DWORD;
PriorityClass, Priority : Integer;
begin
PriorityClass:=GetPriorityClass(GetCurrentProcess);
Priority:=GetThreadPriority(GetCurrentThread);
SetPriorityClass(GetCurrentProcess, REALTIME_PRIORITY_CLASS);
SetThreadPriority(GetCurrentThread, THREAD_PRIORITY_TIME_CRITICAL);
Sleep(10);
asm
dw 310Fh
mov TimerLo, eax
mov TimerHi, edx
end;
Sleep(DelayTime);
asm
dw 310Fh
sub eax, TimerLo
sbb edx, TimerHi
mov TimerLo, eax
mov TimerHi, edx
end;
SetThreadPriority(GetCurrentThread, Priority);
SetPriorityClass(GetCurrentProcess, PriorityClass);
Result := TimerLo / (1000 * DelayTime);
end;
NOTE: NOT TESTED ON MULTICORE PROCESSORS