Apple will report selling another record number of Macs in the final quarter of 2009, according to a Wall Street analyst.

Brian Marshall, of BroadPoint AmTech, estimated total Mac sales at 3.3 million units for 2009's fourth quarter. If Marshall's calculations are accurate, it would mean Apple broke the record sales of 3.05 million Macs set in the year's third calendar quarter by 249,000 machines, an increase of 8.5 percent.

Year-over-year, Marshall's estimate of 3.3 million Macs would be a 31 percent increase from the 2.3 million systems Apple sold in the fourth quarter of 2008. That kind of gain would be a return to Apple sales trends during 2008, when the company racked up impressive year-over-year increases ranging from 21 percent in the third calendar quarter to a whopping 51 percent in the first quarter.

Assuming Apple beats the industry average growth again in the fourth quarter of 2009 - as seems certain, even if Marshall's estimate is on the high side - Apple's sales will have outpaced the average in 20 out of the last 21 quarters. The one exception: The first quarter of 2009, when Apple failed for the first time since 2003 to boost Mac sales year-over-year.

According to Gartner Research, global computer sales will grow by just 2.3 percent during 2009.

Marshall also joined other analysts in predicting a resurgence of Apple's desktop sales by pegging the company's sales for the fourth quarter at 865,000 units, a year-over-year increase of 19 percent and a quarter-over-quarter gain of 10 percent.

Earlier in December, retail research firm said that sales of Apple's desktops - the iMac, Mac mini and Mac Pro lines - were up 74 percent during October and November in the US. At the time, analyst Stephen Baker of NPD credited the revamped iMac for the sales surge.

Apple revealed the new 21.5- and 27-in. iMacs - the latter available with quad-core Intel processors for the first time - on 20 October. Since then, however, questions have cropped up about the 27-in. iMacs' graphics cards and displays, with large numbers of customers reporting flickering screens, a problem multiple authorised resellers said resulted in Apple's decision to delay shipping the largest, most expensive models.

Apple is set to issue its official sales numbers for the fourth quarter in the second half of January.