Another fun issue with the split 64/64 support: lo-hi order. You see, when two orders are possible, of course Intel had to ship both. Yeeep, P3 vs P4. Which u

Another fun issue with the split 64/64 support: lo-hi order. You see, when two orders are possible, of course Intel had to ship both. Yeeep, P3 vs P4. Which used which, is left as an exercise to you, dear reader.