Intel Inc's shares rose on Friday to levels last seen during the dotcom boom 17 years ago, after strong results offered the clearest sign yet that its years-long effort to shift away from a slowing PC business was paying off.

The company's Nasdaq-listed shares (INTC.O) closed Friday trade up 10.55 per cent - or US$4.78 -  at US$50.08.

Investors were also comforted by Intel's assurances that it does not expect any material impact from the recent disclosure of security flaws Spectre and Meltdown in billions of its chips.

The Santa Clara-based company helped found the personal computer industry and became one of the world's biggest chipmaker on the back of growing demand for PCs. But, in the last few years, falling PC demand has pushed Intel to focus on making chips for data centres to offset revenue loss.

Revenue from the company's higher-margin data centre business jumped about 20 per cent to US$5.58 billion.

"Intel is successfully navigating the transition from a PC-centric to data-centric company – specifically, Intel's data-centric businesses now comprise about 47 per cent of revenue," Credit Suisse analyst John Pitzer said.

Pitzer upgraded the stock to "outperform" from "neutral."

The business is showing no signs of slowing down - Intel forecast its data centric unit to grow mid-teens and PC centric business in the low single digits this year, projecting overall revenue growth of 4 per cent to US$65 billion.

"While we believe near term PC unit declines have been impacted by a lengthening in the PC refresh cycle, we view this lengthening as slowing over time, lessening the deleterious impact on overall company growth," Susquehanna Financial Group analyst Christopher Rolland said.

Analysts said Intel will benefit this year from higher demand for gaming computers, memory chip ramp and increased modem sales to Apple Inc's iPhones.

Modem sales increased 26 per cent year-over-year, which we attribute largely to the iPhone refresh, Oppenheimer analyst Rick Schafer said.

Intel has been increasingly displacing Qualcomm as Apple's key modem supplier after its relationship with the iPhone maker soured last year over chip prices.

At least seven brokerages raised their price targets on the stock. Their median price target was US$51.

Of the 39 brokerages covering the stock, 23 rate it as "buy" or higher, 11 "hold" and five "sell" or lower.

The company's shares were trading at US$48 before the opening bell. The stock has gained 20 per cent in the last 12 months, compared with a 40 per cent gain in the Philadelphia Semiconductor index.