Posting third-quarter results Tuesday, Intel (INTC) said it earned 35 cents a share on revenue of $9.39 billion. That’s not quite what the company reported during the same period last year, when it saw earnings of 35 cents a share on revenue of $10.2 billion. But it’s much better than investors had been hoping for. Analysts had expected Intel to report earnings of 28 cents a share on revenue of $9 billion, according to a consensus survey by FactSet Research.

Not bad. Even better, the company bumped up its fourth-quarter guidance from sales of $9.7 billion to sales $10.6 billion. Consensus estimates have been calling for sales of $9.5 billion, according to FactSet Research data.

Intel’s rosier Q4 guidance suggests that the slow increase in end-market demand for PCs we’ve been seeing lately isn’t simply inventory refill but reflects an upswing in demand for end-customer goods. Perhaps that turnaround CEO Paul Otellini has been heralding for the last half year is not as far off as it might seem.

“Intel’s strong third-quarter results underscore that computing is essential to people’s lives, proving the importance of technology innovation in leading an economic recovery,” Intel CEO Paul Otellini said in an earnings release. “This momentum in the current economic climate, plus our product leadership, gives us confidence about our business prospects going forward.”

For the quarter, Intel (INTC) had been expecting revenue in the range of $8.1 billion to $8.9 billion. Now the company expects revenue to range between $8.8 billion to $9.2 billion. Analysts polled by Thomson Reuters had been forecasting $8.55 billion. Welcome news for tech’s long-suffering investors, which spiked the company’s shares more than four percent to $20.25 in early-morning trading.

Intel is next scheduled to report financials on Oct. 13.

Three months after Intel CEO Paul Otellini announced that the PC market had reached bottom, the company’s latest financials, which handily beat expectations, seem to have proven him right. “The worst is now behind us,” he said. And the tech economy is showing signs of muted recovery.

The question is: Is that recovery sustainable?

The answer, according to Otellini, is yes. “The second quarter was clearly better than we expected,” he told analysts on a conference call. “Customers signaled increased confidence in their ordering patterns.” After months of global recession, Otellini noted that the company’s second-quarter results “reflect improving conditions” in the PC market.

“Intel is seeing a firming up in demand,” he added. “It’s encouraging news for the industry.”

Indeed. Intel is a bellwether for the tech sector; as goes Intel, so goes the industry. So, if Intel says demand is beginning to return to normal seasonal patterns, then the industry may truly be stabilizing. That said, there’s still quite a bit of economic volatility–enough to suggest that it might be wise not to read too much into Intel’s performance.

Said analysts at JP Morgan: “Although the Intel quarter was clearly spectacular on all fronts, we continue to believe the upside was driven by inventory replenishment as we have not seen any evidence of increasing PC demand.”

Shares of Intel (INTC) are trading up 6.77 percent at $17.97 this morning.