This earnings season hasn't been especially kind to technology. Whether it be Google falling after its earnings last week or IBM and Intel leading the way to disappointment this week, there haven't been a lot winners across the tech landscape, and the scene continues to darken tonight.

After-hours notable tech companies reporting include Riverbed (Nasdaq: RVBD), Altera, AMD, Rambus (Nasdaq: RMBS), SanDisk (Nasdaq: SNDK), and Microsoft (Nasdaq: MSFT). Not every company failed to live up to expectations, but most were losers. Let's look at a few earnings reports.

The biggest loser: Riverbed
Riverbed managed to meet earnings expectations last quarter, notching an adjusted $0.20 per share in earnings. However, revenue fell short, and its outlook for next quarter came in at a midpoint of $195 million, well below the Street's expectation of $202 million. In response, Riverbed dropped a staggering 17% after hours. Is the pessimism warranted?

A strong reaction to Riverbed's earnings isn't uncommon: Last summer, shares plunged 24% on a 1.5% revenue miss. Shares also took a tumble last quarter on disappointing earnings. In both this quarter and the last, management blamed a transition in its flagship Steelhead product line for a hiccup in sales.

That excuse can explain a few quarters' worth of hiccups, but there are some areas of concern. Notably, growth in Riverbed's core WAN optimization business continues to slow, which is a trend that's troubling for a company with a P/E hovering around 70 at today's close. Single-digit growth won't be acceptable for very long from a company this richly priced. Second, the company continues not to execute very well in its "Rest of World" segment outside North America and Europe. That's an area where many other companies are seeing their strongest growth, yet Riverbed posted just 4% growth in its global division.

Expectations for Riverbed ran high today when networking peer F5 Networks (Nasdaq: FFIV) stomped expectations. Yet in retrospect, some of the areas boosting F5-like telecom spending aren't key drivers for Riverbed. I still like Riverbed's long-term prospects, but this quarter does turn up the heat on Riverbed to deliver in the second half of the year if it wants investors to keep buying into the idea that WAN optimization has a long runway of growth ahead of it.

Two more drops: SanDisk and Rambus

SanDisk isn't far behind Riverbed's drop. The company is down 13.5% after it not only reported earnings below estimates last quarter but also issued weak guidance. While the company reported net income of $114 million in the quarter, its free cash flow checked in at negative-$77 million. The fear continues to be that flash memory will continue to commoditize, as DRAM did a decade ago. While SanDisk collects a nice "buffer" of $100 million in high-margin licensing and royalty a quarter, its product revenue is becoming a profitless wonder.

Finally, Rambus missed earnings by $0.02 and initially saw a drop of more than 6%. However, that drop has since abated, and the company is down just 1%. With most of Rambus' swings coming from its in-court battles, there's little reason to sell off the company on earnings news.

Finally, on to the winners' column!
While megacap peers IBM and Intel disappointed earlier this week, Microsoft delivered the goods tonight. Microsoft's three biggest business units all saw healthy gains: Business sales jumped 9%, Windows rose 4%, and Servers and Tools were up 14%. The biggest disappointment was its Entertainment unit, falling 16%. However, with healthy growth in its main segments, that blip was more than forgivable. I've avoided Microsoft because of its inability to profit -- thanks to piracy -- in the geographic areas with the highest growth rates, but I must say this quarter was an impressive one if you're a Microsoft bull.

Keep searching for global opportunities
Today, tech stocks were mainly down on earnings season, but there are thousands of companies left to report. If you want to get the inside scoop on the rest of earnings, check out the 5 Stocks Investors Need to Watch This Earnings Season. You can learn more about these stocks by clicking here. Enjoy, and fool on!