rcollins@altos86.Altos.COM (Robert Collins) (10/19/90)
To all you GURU's out there that (think you) know have software to determine the difference between the 386DX & 386SX, read this: I remember that a few people claimed it was 'easy' but wouldn't post thier code (my version of put up, or shut up). I also remember some code posted that used the prefetch queue to determine the difference between the two. As I responded, if the code worked, it worked by accident -- not by design. The code would fail on fast systems and some systems with cache memory. Now, to my point of this posting: Intel confirmed to me today that they have reduced the size of the prefetch queue on the 80386DX as of the D1 stepping. It has been reduced to 12-bytes from the original 16. This reduction in prefetch queue size fixed a bug with pipelined execution. The GURU @ Intel that called me is now checking to see if the same change was made on the SX (even though the SX didn't have the same bug as the DX). So, even if you thought your algorithm worked, you can now through it away. -- "Worship the Lord your God, and serve him only." Mat. 4:10 Robert Collins UUCP: ...!sun!altos86!rcollins HOME: (408) 225-8002 WORK: (408) 432-6200 x4356