S&P stock index futures pointed to a slightly lower open on Tuesday with investors set to take profits after a recent runup while the results of government stress tests on the financial sector remained a focus.

* According to a source familiar with official talks between banks and regulators, about 10 of the 19 largest U.S. banks being tested will be instructed by regulators to raise more capital.

* The banks have been negotiating with the regulators about the depth of their capital needs, should the recession prove to be deeper and longer than anticipated.

* Stocks rose on Monday, driving the S&P 500 into positive territory for the year as investors bet banks' capital shortfalls may be manageable and housing data fueled hopes the recession is easing.

* Federal Reserve Chairman Ben Bernanke will testify on the economy before the Joint Economic Committee at 10:00 a.m. EDT. Investors will be keen for any new indication the recession is easing.

* On the data front, a reading on the Institute for Supply Management's nonmanufacturing index for April is expected later in the morning.

* S&P 500 futures fell 2 points and were below fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract. Dow Jones industrial average futures climbed 11 points, and Nasdaq 100 futures fell 1 point.

* Investors were hopeful that the amount of capital banks need to raise will be manageable but were anxious over any negative surprises that could be revealed.

* Any news that points to more stabilization in the banking sector will be a positive for stock investors since authorities have said shoring up the financial system is key to reviving the recession-hit economy.

* On the earnings front, shares of MGM Mirage rose ahead of the opening bell after the casino operator reported first-quarter earnings late on Monday and said it is evaluating a variety of options, including asset sales, to address liquidity needs.

* Shares of D.R. Horton Inc fell in extended trade on Monday after the homebuilder reported a wider-than-expected loss in the second quarter.

* The S&P 500 is now up 34 percent from its 12-year closing low on March 9 but it is still off 42 percent from its October 2007 record high.

(Reporting by Leah Schnurr; Editing by Theodore d'Afflisio)