The jump in tech shares indicates that tech investors have confidence that, underlying worries about the economy, there is strong demand for technology. Despite concerns that the fourth quarter, plagued among other things by natural disasters that crimped the supply of hard drives, would be tough for tech, bellwether IT companies on the whole did well.

Apple was the star of earnings season, posting record quarterly revenue of $46.33 billion and record net profit of $13.06 billion, compared to revenue of $26.74 billion and net quarterly profit of $6 billion in the year-earlier quarter. But market leaders in other sectors of IT had good quarters as well.

Cisco, which came under fire last year when its sales slipped, reported that cost-cutting efforts had paid off. Cisco's net sales for its second fiscal quarter were up 10.8 percent year over year to $11.5 billion, while earnings rose 43.5 percent to $2.2 billion. On the software front, SAP said it has its best year ever, supported analyst forecasts for a strong year for enterprise software.

With most of the large tech vendors having already reported quarterly earnings, results this week came from second-tier players. Though results were mixed, tech investors appeared to stress the positive aspects of the reports.

On Wednesday, for example, graphics chip maker Nvidia said revenue for the fourth quarter of its fiscal 2012 was $953.2 million, up 7.5 percent from $886.4 million in the same period a year earlier. However, net income declined to $116.0 million from $178.3 million. Sales of the company's Tegra 3 processor have failed to live of up to expectations, partly as a result of the lingering impact of the hard disk-drive shortage caused by Thailand floods.