faed057a37
avoid lost timer interrupts. Previous optimization attempt doing it only for intervals less then 5000 ticks (~300us) reported to be unreliable by some people. Probably because of some heavy SMI code on their boards. Introduce additional safety interval of 128 counter ticks (~9us) between programmed comparator and counter values to cover different cases of delayed write found on some chipsets. Approved by: re (kib)