STOCKS TO WATCH: AMD, Altera, Rambus, Redback Networks and Seagate

You can count on AMD shares taking off Thursday after the chipmaker destroyed analysts' earnings estimates in its first quarter.

Strong sales of its high-performance Athlon chips helped AMD earn $189.3 million, or $1.15 a share, on sales of $1.09 billion.

First Call consensus expected the chipmaker to earn 58 cents a share in the quarter.

The $1.09 billion in sales marks a stellar 73 percent improvement compared to the year-ago quarter when it lost $128.3 million, or 88 cents a share, on sales of $631.6 million.

"AMD had the best quarter in its history," said CEO Jerry Sanders in a prepared release. "Each of our product groups reported significant growth in the first quarter."

Company officials said unit sales of Athlon chips jumped 50 percent to 1.2 million units. Total chip sales improved 14 percent from the fourth quarter and 65 percent from the year-ago quarter.

While the rest of the booming worldwide semiconductor industry is projecting sales growth of between 20 percent to 25 percent this year, AMD now says its total sales will improve by more than 50 percent.

Altera's going to climb higher Thursday after it beat Street estimates in its first quarter and was added to the S&P 500.

The PLD manufacturer posted a first-quarter profit of $75.2 million, or 36 cents a share, on sales of $272.8 million.

First Call consensus expected it to earn 34 cents a share in the quarter.

Its shares closed off 4 5/16 to 82 ahead of the earnings report.

The $272.8 million in sales represents a 46 percent jump from the year-ago quarter when it earned $47 million, or 23 cents a share, on sales of $186.4 million.

First quarter sales growth of 15 percent was achieved through gains of 17 percent in North America, 30 percent in Europe, and 12 percent in the Asia/Pacific region. Sales to Japan fell 6 percent.

Rambus should be worth watching Thursday after it topped Street estimates in its second quarter, posting a profit of $4.9 million, or 15 cents a share, on sales of $15.7 million.

First Call consensus expected the chipmaker to earn 14 cents a share in the quarter.

Rambus shares closed off 32 3/16, or 13 percent, to 213 13/16 ahead of the earnings report.

The $15.7 million in sales marks a 59 percent improvement from the year-ago quarter when it pocketed $2.9 million, or 8 cents a share, on sales of $12 million.

Company officials said it exited the quarter with $96 million in cash. Meanwhile, deferred revenue decreased to $35 million from $44 million in the prior quarter.

Reback easily beat Street estimates in its first quarter, pocketing $5.6 million, or 5 cents a share, on sales of $34.2 million.

First Call consensus expected the network-equipment maker to earn 3 cents a share in the quarter.

Its shares closed off 18 3/4, or 16 percent, to 96 ahead of the earnings report. The stock fell another $3 a share in after-hours trading.

In the year-ago quarter, Redback lost $2.7 million, or 16 cents a share, on sales of $6.5 million.

The disk-drive maker might slip a bit Thursday even though it did beat analysts' estimates in its third quarter.

Seagate earned $46 million, or 20 cents a share, on sales of $1.57 billion.

Its shares closed off 2 to 49 3/4 ahead of the earnings report.

First Call consensus expected Seagate to rake in 15 cents a share in the quarter.

In the year-ago quarter, Seagate posted a profit of 49 cents a share on sales of $1.81 billion.

Last month, Seagate stunned Wall Street by announcing a complicated $20 billion deal that would take the company private while selling its one-third stake in Veritas Software Inc. (Nasdaq: VRTS) back to Veritas.

Including one-time items, Seagate earned $136 million, or 58 cents a share. Those figures include a restructuring charge of $49 million, a charge of $105 million for the write-off of in-process research and development in connection with the company's acquisition of XIOtech Corp., a gain on sale of a portion of its investment in SanDisk Corp. of $453 million, and charges related to its investment in Veritas Software Corp. of $78 million.