Updated from 10:34 a.m. EDT

iPhone fever may have obscured the robust growth in

Apple's

(AAPL) - Get Report

Macs.

People familiar with the company say Apple is selling computers at a blockbuster pace. The Cupertino, Calif., company is expected to sell 2.35 million iMacs and MacBooks this quarter,

TheStreet.com

has learned.

A sales number that high would beat analysts' estimates by nearly 400,000 units. Pegging the average Mac sales price at a conservative $1,500, a beat of that magnitude stands to boost Apple's top line by about $600 million. Analysts expect the company to post fiscal first-quarter revenue of $5.94 billion.

The popularity of Apple's computer lineup has been fueled by a robust back-to-school buying spree and a revamped iMac roster, say industry watchers.

Apple has about 3% of the world's computer market share, but it has gained ground as larger rivals like

Hewlett-Packard

(HPQ) - Get Report

and

Dell

(DELL) - Get Report

try to revive sluggish sales.

Apple's strong growth prospects and its marketing and design cachet have earned the company a significant premium to many of its tech peers. Apple's market cap is $122 billion -- twice that of Dell, even though Dell's sales are around three times Apple's.

Want more? Check out TheStreet.com TV video.Scott Moritz takes a closer look.

Looking ahead, people inside the company and those close to Apple's plans say there will be a big announcement regarding a so-called subnotebook Mac. The ultra-thin device will have a 10-inch to 12-inch screen; sleek, rounded edges; and weigh less than 2 pounds.

The subnotebook's introduction is planned for next quarter, and the product is expected to be available for the holiday sales season. In preparation for a big year-end sales push, Apple has told some employees to cancel vacation plans "between Thanksgiving and Christmas," says one source familiar with the memo.

Apple shares rose $3.19, or 2.3%, to $143.50 Friday afternoon.