No further production of x.86 clone chips from IBM Micro is likely, following the severing of ties between it and National Semiconductor/Cyrix, it has emerged. And Cyrix will now try to switch existing customers of 6x86 to its own products, according to sources close to the firm.

The large sum of money paid by Cyrix to IBM, first exclusively reported here, does not include any patent cross licensing, the same sources said.

Some of the $50 million or so IBM will receive, described in an official Cyrix statement as “the transfer of certain assets” relates to payment for existing IBM stock as well as .35 micron wafer processing equipment, the source added.

The severing of ties between Cyrix and IBM Microelectronics will mean that the Big Blue 6x86 version of the processor is likely to disappear by year end, with a transition period where Cyrix talks to IBM customers. One source close to NatSemi said: “You’ll have to ask IBM about whether it will continue making x.86 chips after the end of the year, but clearly there’s one less x.86 competitor in the market.”

Ever since the deal between Cyrix and IBM Microelectronics was set up, there has been constant bickering between the two companies. Big Blue undermined Cyrix margins and channel relations and also, at one point, claimed its version of the 6x86 chip was superior to the identical part from Cyrix. But although NatSemi-Cyrix has essentially severed the x.86 tie, it has not closed doors to overtures from Big Blue in the future, the source said.

The same source added that Cyrix can make over 10 million x.86 parts per year at its South Portland fabrication plant, and will be able to triple that number when the ramp slopes right up.

When NatSemi bought Cyrix last year, its primary goal was to cut out IBM Microelectronics from the loop. However, it is content to stay with Taiwanese foundry TSMC and has a good relationship with the firm, the source said. The charge NatSemi-Cyrix will now make is to made to cost of sales in Cyrix’s Q2 and will impact its gross margins, the sources claimed. This coming week, Cyrix is set to announce a major design win, the source said. ®