>I would have though that "spread spectrum" (implying a continually >changing random frequency) was definitely something to avoid for accurate >timekeeping! As you say, changing the HAL is not something to be >undertaken lightly.
Is "spread spectrym" as used for CPU clocks really going to do anything evil to timekeeping? Is it really random? I've been assuming it was some simple modulation pattern - sine or sawtooth. It's all on one chip in a cutthroat business so they aren't going to pay much for it. What does Windows use for timekeeping? Linux (on most boxes) uses the interrupts from the TOY/battery-backed clock, usually running off a 32 KHz watch crystal. I got surprised by this a few years ago. The main complication with using the main CPU clock is SMP systems. It's fairly easy to compare the two crystals. Both track temperature very well. -- The suespammers.org mail server is located in California. So are all my other mailboxes. Please do not send unsolicited bulk e-mail or unsolicited commercial e-mail to my suespammers.org address or any of my other addresses. These are my opinions, not necessarily my employer's. I hate spam. _______________________________________________ questions mailing list [email protected] https://lists.ntp.isc.org/mailman/listinfo/questions
