Chris Lau, Kapitall: Could a weakening market for smartphones hamper these four semiconductor stocks? Once touted as providing infinite growth in the tech sector, smartphone sales may finally be weakening. Smartphone bellwether Samsung (OTC: SSNLF) reported higher net profits and sales, but operating profits declined in its last quarter of 2013. Even more worrisome is that the company warned that the first quarter of 2014 will be weaker than expected. Should investors be worried? Fortunately there are a number of characteristics that vulnerable stocks have in common, making them easier to spot. Valuation Companies valued with a high forward P/E (or price of profit) are at risk of selling off. Take a look at NVIDIA (NVDA) for instance. Its forward P/E is 22: Click on the interactive charts below to see data over time. Sourced from Zacks Investment Research. By comparison, Quacomm (QCOM), SanDisk (SNDK), and Micron (MU) are valued far less. Micron stands out as having one of the lowest valuations in the semiconductor group. Outlook NVIDIA, which is set to report earnings on February 12, is undergoing a multi-year transition from traditional desktop chip sales to mobile sales. The release of its Tegra K1 processor is aimed to help the company compete more effectively against Qualcomm. Investors are clearly optimistic NVIDIA will be successful, however Qualcomm is already very successful with its Snapdragon chip. Still, Qualcomm could face headwinds if sales for Samsung stagnate and the company misses its sales forecasts for the phones and tablets. Learn more: Compare analyst ratings to annual returns for stocks mentioned.SanDisk, Micron SanDisk, which reported Q4 earnings of $1.61 per share, is optimistic that sales for SSDs (solid state drives) will grow. The company had a strong 2013, with embedded revenue growing 37%. SSD revenue grew at a faster rate, up 170% last year. Gross margin was 50.9%. Samsung relied on more than half of its unit sales in the emerging markets.