Dell said its adoption of AMD processors helped it reach $677m (£355m) in profit for the third quarter, although the company has delayed reporting final numbers due to an accounting investigation by the US SEC (Securities and Exchange Commission).

Dell's preliminary results mark an improvement over the third quarter last year, when it reported $13.91bn (£7.3bn) in revenue and a profit of $606m (£320m). The world’s number two PC maker reported revenue of $14.38bn (£7.6bn) for the quarter, but did not offer an official comparison to the year-earlier figures.

The company was scheduled to report its earnings last Thursday, but delayed the move because it was trying to cooperate with investigations by the SEC and the US Attorney for the Southern District of New York. Company executives had cited the same reason after they missed a deadline for notifying the SEC of their second quarter earnings. They have still not filed that report, called a Form 10-Q.

Dell pointed to its success in selling computers powered by AMD processors for its impressive numbers. After missing its earnings target for the first quarter, Dell said in May it would finally diversify from selling computers with chips from Intel.

Still, Dell is having a rocky year. In June, chief executive Kevin Rollins promised to rebound from weak earnings by investing $100m (£53m) in customer service and by using fewer rebates in setting PC prices. But in August, Dell was forced to recall 4.1m defective laptop batteries. Then, Dell acknowledged it was under investigation by the SEC, and, last week, lost its status as world's largest PC vendor to rival HP.