UPDATE 2-Intel's forecast misses on slowing China, data center; shares tumble

(Adds PC segment results, analyst comment, background)

Jan 24 (Reuters) - Intel Corp forecast current-quarter revenue and profit below analysts' estimates and missed on fourth-quarter sales expectations on Thursday, hit by a slowdown in China and sluggish demand for its data center and modem chips.

The company's shares fell 7.7 percent in extended trading and also undid part of a chip stock rally earlier in the day following better-than-feared quarterly results from a clutch of companies such as Texas Instruments Inc, Xilinx Inc and Lam Research Corp.

Smaller rival Advanced Micro Devices, which reports results next Tuesday, dropped 2 percent, while Nvidia fell 1 percent.

Sales warnings from Apple Inc, Samsung Electronics Co Ltd and Taiwan Semiconductor Co Ltd earlier this month had pointed to stagnating smartphone demand and a cooling Chinese economy.

Reports that Apple is reducing planned production for its three new iPhone models by about 10 percent for the January-March quarter weighed on Intel, which has replaced Qualcomm as the sole supplier of modem chips for the newer phones.

Intel forecast first-quarter revenue of $16 billion and adjusted earnings of 87 cents per share.

Analysts on average were expecting revenue of $17.35 billion and a profit of $1.01 per share, according to IBES data from Refinitiv.

"The macro environment does not look good at the moment and if it gets worse, Intel could see a further downside to its outlook," said Kinngai Chan, an analyst with Summit Insights Group.

Intel has turned to the server chips it supplies data center operators for growth in recent years. However, fourth-quarter revenue in that higher-margin business came in at $6.07 billion, below expectations of $6.35 billion, according to financial and data analytics firm FactSet.

The company said data center missed expectations "on softer China demand" and "cloud deceleration".

Revenue in the company's client computing business, which includes sales to PC makers was $9.82 billion, missing FactSet estimates of $10.01 billion.

Intel reported https://bit.ly/2FN4ac0 net income of $5.20 billion, or $1.12 per share, for the fourth-quarter ended Dec. 29, compared with a loss of $687 million, or 15 cents per share, a year earlier.

Net revenue rose to $18.66 billion from $17.05 billion, but missed estimates of $19.01 billion.

Excluding items, the company earned $1.28 per share, above expectations of $1.22. (Reporting by Sonam Rai in Bengaluru and and Stephen Nellis in San Francisco; Editing by Sriraj Kalluvila)