Intel Corp., a key component in the AdMarket 50, closed the week with the largest gain of any index member despite a sell-off on Friday. The chipmaker last Thursday held a rare midquarter briefing, where it said revenue for its second quarter would be within forecasts. It also predicted a stronger second half. Intel had slashed revenue estimates for each of its previous three quarters. Its stock trades at less than half its 52-week high of $75.81, reached last September, but has climbed from its low of $22.25 reached earlier this spring. In trading Friday, Intel closed at $30.67, up $7.61% for the week. Twenty-four AdMarket 50 stocks finished the week up, while 26 were down.