Determine the processor speed in MHz

Here is a handy routine which will return an estimated core processor speed (CPU speed) of your PC. Read the comment to see how to use it.



function GetCpuSpeed: Comp;

{ function to return the CPU clock speed only. }

{ Usage: MessageDlg(Format('%.1f MHz', [GetCpuSpeed]), mtConfirmation, [mbOk], 0); }

var

t: DWORD;

mhi, mlo, nhi, nlo: DWORD;

t0, t1, chi, clo, shr32: Comp;

begin

shr32 := 65536;

shr32 := shr32 * 65536;

t := GetTickCount;

while t = GetTickCount do

begin

end;

asm

DB 0FH

DB 031H

mov mhi,edx

mov mlo,eax

end;

while GetTickCount < (t + 1000) do

begin

end;

asm

DB 0FH

DB 031H

mov nhi,edx

mov nlo,eax

end;

chi := mhi;

if mhi < 0 then

chi := chi + shr32;

clo := mlo;

if mlo < 0 then

clo := clo + shr32;

t0 := chi * shr32 + clo;

chi := nhi;

if nhi < 0 then

chi := chi + shr32;

clo := nlo;

if nlo < 0 then

clo := clo + shr32;

t1 := chi * shr32 + clo;

Result := (t1 - t0) / 1E6;

end;