Updated from 12:36 p.m. EDT

Tech stocks were on the rise Wednesday, boosted by solid earnings and analyst upgrades.

Navteq ( NVT - Get Report) climbed 16.9% after the business software firm posted solid profit gains after the prior bell. The company reported net second-quarter income of $40.9 million, or 41 cents a share, compared to $23.8 million, or 25 cents a share, in the year-ago period.

The company also upped its full-year guidance. It now expects revenue of $780 million to $795 million and earnings per diluted share of $1.45 to $1.50. Analysts polled by Thomson Financial expect revenue of $747.8 million and earnings of $1.33 a share. Shares closed up $9.16 to $63.29.

FiberTower jumped 17.1% after announcing an agreement with Sprint Nextel ( S - Get Report) to provide backhaul services in seven of the company's initial WiMax launch markets. Sprint plans to roll out the service by the end of the year, followed by a rollout to almost 100 million customers by the end of 2008. Terms of the agreement with FiberTower were not disclosed. Shares gained 60 cents to $4.12.

Disc drive component maker Hutchinson Technology ( HTCH) jumped 11.3% after being upgraded by three firms following a solid earnings report. Needham & Co. and WR Hambrecht both upgraded the stock to buy from hold, and Brean Murray upgraded it to hold from sell. Hutchinson gained $2.26 to $22.32.

The Nasdaq 100 was up about 13 points, to about 1945, boosted in part by Apple ( AAPL - Get Report). The iPod and iPhone maker climbed 2.5% after Tuesday's selloff on rumors of a cut in iPhone production, following Citigroup's upgrade of the stock to buy from hold.

The tech sector, however, also had some precipitous drops.

TTM Technologies ( TTMI - Get Report) plummeted 18.6% after reporting a shrinking second-quarter profit after the prior bell. The printed circuit board maker earned $6 million, or 14 cents a share, compared to $10.6 million, or 25 cents a share in the year-ago period. The company also forecast third-quarter results below Wall Street's expectations. It sees revenue of between $160 million to $168 million and earnings of between 14 cents and 20 cents a share. Analysts polled by Thomson Financial expect earnings of 21 cents a share on revenue of $170.2 million. Shares fell $2.42 to $10.62.

Software maker SumTotal Systems swooned 23.8% after Brean Murray downgraded it to hold from buy after a disappointing earnings report. While the company narrowed its loss form a year ago, results still fell short of analysts' estimates. The company lost $1.5 million, or 5 cents a share, on revenue of $30.2 million, compared to Reuters' forecast of 8 cents a share on revenue of $30.7 million. Shares fell $1.84 to $5.90.