NOT AGAIN: A little-known Canadian computer company has sued Intel for alleged intellectual property violation. All Computers claims the Pentium II contained circuitry for which it owns the right. Furthermore, it says, Intel does not have permission to use said circuitry.

All currently has two patents filed with the US Patent and Trademark Office, both entitled 'Apparatus and method for enhancing the performance of personal computers' and both centering on adjusting the clock speed of "an accelerator board for use in replacing the microprocessor of a slow speed system board with a microprocessor operating at a higher clock speed".

All claims that the Pentium II uses techniques outlined in the patents - 5,450,574 and 5,506,981 - to synchronise a processor's clock with the chipset's system clock.

Crucially, the technique allows CPU clocks to operate at fractional multiples of the system clock rather than whole-number multiples.

The Pentium II is of course defunct as a desktop processor, and All's patents were filed in 1993. So why the wait? We only just found out about it, the company claims. It's also evaluating the Pentium III for possible infringements.