--- est.c.ORI	2009-07-14 08:57:29.000000000 +0200
+++ est.c	2010-04-15 10:29:11.000000000 +0200
@@ -1207,11 +1207,15 @@
 	freq = tsc_freq / 1000000;
 	id = msr >> 32;
 	bus = freq / (id >> 8);
+	if( id & 0x4000 )
+	  bus = 2 * freq / ( (id >> 7 & 0x7e) + 1 );
 	device_printf(dev, "Guessed bus clock (high) of %d MHz\n", bus);
 	if (!bus_speed_ok(bus)) {
 		/* We may be running on the low frequency. */
 		id = msr >> 48;
 		bus = freq / (id >> 8);
+		if( id & 0x4000 )
+		  bus = 2 * freq / ( (id >> 7 & 0x7e) + 1 );
 		device_printf(dev, "Guessed bus clock (low) of %d MHz\n", bus);
 		if (!bus_speed_ok(bus))
 			return (EOPNOTSUPP);
@@ -1219,6 +1223,8 @@
 		/* Calculate high frequency. */
 		id = msr >> 32;
 		freq = ((id >> 8) & 0xff) * bus;
+		if( id & 0x4000 )
+		  freq =( (id >> 7 & 0x7e) + 1 ) * bus / 2;
 	}
 
 	/* Fill out a new freq table containing just the high and low freqs. */
@@ -1241,6 +1247,8 @@
 	/* Second, the low frequency. */
 	id = msr >> 48;
 	freq = ((id >> 8) & 0xff) * bus;
+	if( id & 0x4000 )
+	  freq =( (id >> 7 & 0x7e) + 1 ) * bus / 2;
 	volts = id & 0xff;
 	if (volts != 0) {
 		volts <<= 4;