* As an exception, if every logical processor on the system
		 * is on the same chip, we use the performance counter anyway,
		 * presuming that everyone's TSC is locked to the same
		 * oscillator.
		 */

		SYSTEM_INFO systemInfo;
		unsigned int regs[4];

		GetSystemInfo(&systemInfo);
		if (TclWinCPUID(0, regs) == TCL_OK
			&& regs[1] == 0x756e6547	/* "Genu" */
			&& regs[3] == 0x49656e69	/* "ineI" */
			&& regs[2] == 0x6c65746e	/* "ntel" */
			&& TclWinCPUID(1, regs) == TCL_OK
			&& ((regs[0]&0x00000F00) == 0x00000F00 /* Pentium 4 */
			|| ((regs[0] & 0x00F00000)	/* Extended family */
			&& (regs[3] & 0x10000000)))	/* Hyperthread */
			&& (((regs[1]&0x00FF0000) >> 16)/* CPU count */
			    == systemInfo.dwNumberOfProcessors)) {
		    timeInfo.perfCounterAvailable = TRUE;
		} else {
		    timeInfo.perfCounterAvailable = FALSE;
		}
	    }
#endif /* above code is Win32 only */