Wall Street powerhouse Standard & Poor's lowered its opinion of Dell (Nasdaq: DELL), the No. 3 PC maker, because it's becoming "more bearish of the PC industry in general," the ratings agency said Wednesday. It trimmed its 12-month target price for Dell shares to $14 from $15.

Dell shares traded around $12.11 down 8 cents, in early Wednesday trading. The Round Rock, Tex., PC maker and services provider's 52-week high was $18.36. The company is scheduled to report second-quarter earnings next Tuesday.

S&P shaved its fiscal 2013 earnings estimates to $1.88 a share from the previous $1.92 and estimates for fiscal 2014 to $1.96 from the previous $2.14. The agency suggested Dell's revenue will decline, margins will narrow and the company will have trouble battling the new Microsoft (Nasdaq: MSFT) tablet, dubbed Surface, scheduled for introduction soon.

The unit of McGraw Hill Cos. (NYSE: MHP) didn't make comments about other PC makers, headed by No. 1 vendor Hewlett-Packard Co. (NYSE: HPQ), which scheduled to report third-quarter results next week. HP shares fell a penny to $19.35 in early trading.