By Noel Randewich

SAN FRANCISCO (Reuters) - Intel Corp forecast current-quarter revenue that was slightly below expectations as the personal computer industry grapples with falling sales and a shift toward tablets and smartphones.

PC makers are struggling to stop a decline in sales as consumers hold off on buying new laptops in favor of spending on more nimble mobile gadgets.

Microsoft Corp's long-awaited launch of Windows 8 in October brought touchscreen features to laptops but failed to spark a resurgence in sales that Intel and many PC manufacturers had hoped for.

Intel said its capital spending in 2013 would be $13 billion, plus or minus $500 million, exceeding what many analysts had expected.

In the fourth quarter, Intel's revenue was $13.5 billion, compared with $13.9 billion a year earlier. Analysts had expected $13.53 billion in revenue for the fourth quarter, according to Thomson Reuters I/B/E/S.

Intel estimated first-quarter revenue of $12.7 billion, plus or minus $500 million. Analysts expected $12.91 billion for the current quarter.

Net earnings in the December quarter were $2.5 billion, or 48 cents a share, compared with $3.4 billion, or 64 cents a share, in the same quarter last year.

(Reporting by Noel Randewich; Editing by Richard Chang)