Intel predicts that it will ship two million combined 32/64-bit Xeon processors by the end of the month, and has promised to extend the range.

The company sold its first million units in six months and has sold the second million in three. Shipments for the new chips overtook pure 32-bit versions in the last quarter of 2004.

"This ramp up is good news; we're executing on all cylinders," said Kirk Skaugen, general manager at Intel's enterprise platforms group.

"By the end of February we'll have shipped two million units of the 32/64bit Xeon. Demand is very strong; we shipped one million in the first six months that it was available."

Barely a year ago Intel was claiming that there was no demand for combined 32/64-bit processors and was sticking to its policy of making separate 32- or 64-bit chips.

But the company has changed its tune and now insists that increased operating system support from Microsoft and lower prices for DRam means that the market is ready for the combination chips.

Intel now expects 80 per cent of the Xeons shipped this quarter to be the combined 32/64-bit version.

The company is also extending the line with two newly developed Xeons, codenamed Potomac and Cranford. Potomac has increased L3 cache for faster data handling, while Cranford has a smaller cache at 1MB but runs at higher frequencies to compensate and is designed as an entry level processor.

The Xeons are designed to work in a quad-processor servers and will be part of the new 8500 chipset. They will launch officially in the next three months.