By Noel Randewich

SAN FRANCISCO (Reuters) - Record earnings, a better-than-expected outlook and potential to buy back $10 billion in stock have put some shine back on the world's top chipmaker although investors are wary of jumping in for the long haul.

Stock in the world's largest chipmaker has lagged its tech counterparts, punished by fears the longtime PC gargantuan is being left out of the mobile device boom. But stellar earnings this week lent credence to its argument that the PC market is still growing at a healthy rate.

The question is for how long. At least for now, the Street is giving Intel -- which hopes to get into mobile devices through its new Ultrabook initiative -- the benefit of the doubt.

Investors a little less worried that tablets and a shaky economy are eating in to demand for personal computers pushed Intel's stock up 3.6 percent on Wednesday, bringing its gain this year to 16 percent, but it still looks cheap compared with other tech companies.

"The reason the multiple isn't greater than it is is there isn't the sizzle of the next iPhone or the next iPad, that market-expanding opportunity into future, more touch-friendly devices," said JMP analyst Alex Gauna, who recommends the stock.

The Santa Clara, California company's earnings and outlook beat expectations on Tuesday, as has become common in recent quarters, with demand for China helping offset weakness in Europe and helping deliver record cash flow.

Intel also authorized $10 billion to buy back shares, which currently pay a dividend yield of over 3.5 percent.

Shares of Intel trade at 10 times earnings, lower than an average of 14 for tech companies but better than Hewlett-Packard Co and Dell Inc, which also depend heavily on PC sales pinched by a lackluster economy and the growing popularity of tablets.

One of a handful of analysts who do not recommend buying Intel, CLSA's Srini Pajjuri is concerned that the company's outlook for personal computer sales has been consistently higher than forecasts by market research groups in recent quarters.

"My best guess at this point is that there's an inventory build somewhere. Within the next one to two quarters I expect Intel (earnings) to underperform the market."

Intel's processors are used in 80 percent of the world's PCs but the company has failed to gain traction in mobile gadgets like Google Inc's Android smartphones and Apple Inc's iPad.

Chips made by Samsung, Texas Instruments and Nvidia using an energy-efficient technology licensed by Britain's ARM Holdings dominate the smartphone and tablet market.

Proponents of ARM say its power-sipping architecture used to design its chips gives such a large advantage that Intel will be unable to dominate the mobile market. Competitors also plan to make inexpensive ARM chips for PCs -- challenging Intel on its own turf.

Intel says its formidable lead in manufacturing technology, letting it pack more transistors onto a silicon chip than its competitors can, will eventually allow it to deliver superior processors for mobile devices.

Concerns that ARM, tablets and other mobile gadgets will decimate the PC market dominated by Intel, or at least cut in to the chip giant's margins, are a key factor weighing on many investors.

Intel is promoting Ultrabooks, a new super-thin category of laptops using Intel processors -- similar to Apple's MacBook Air.

Early Ultrabook models, meant to combine the best features of tablets and laptops, may seem expensive to consumers, analysts say. But as they get new features, such as touchscreens and "instant on" capability, Intel expects the Ultrabooks to account for 40 percent of the consumer PC market by the end of next year.

Gauna said it is tough to predict how technology advantages in the mobile market will play out down the road but sees Intel's dependable cashflow and investor-friendly share buyback and dividends as reasons to own the stock now.

"I don't need the tablets or iPhones to make this an attractive investment today," he said.

(Reporting by Noel Randewich, editing by Matthew Lewis)