* Morgan Stanley rise after results beat expectations
* Vivint Solar soars after SunEdison deal
* IBM to report after the bell
* Greece banks reopen after three weeks
* Futures up: Dow 37 pts, S&P 3 pts, Nasdaq 13 pts (Adds details, comment, updates prices)
By Tanya Agrawal
July 20 (Reuters) - Wall Street was set to open slightly higher on Monday, adding to last week's gains, as better-than-expected earnings from big companies boost investor confidence.
On Friday, strong earnings from Google pushed the tech-heavy Nasdaq to a record close, which gained 4.3 percent for the week, its largest weekly gain since October while the S&P 500 stopped just short of its record high.
Tech earnings will continue to be in focus this week with IBM reporting after the close on Monday and other big tech giants such as Apple, Yahoo and Microsoft expected to report later this week.
"If things stay quiet on the Greece and China front, it will be good for the market to focus on earnings, which should be driving the market in the first place," said Randy Frederick, managing director of trading and derivatives for Charles Schwab in Austin, Texas.
Of the companies that have reported earnings so far, 71 percent have reported earnings above analyst expectations, above the 63 percent that typically beat in a quarter.
However, only 51 percent have beaten on revenue, below the 61 percent.
U.S. companies were expected to post their worst sales decline in nearly six years in the second quarter, in part due to the strong dollar that reduces the value of U.S. companies' overseas income. Profit is expected to have fallen 2.9 percent, according to Thomson Reuters estimates.
The dollar index was up marginally at $97.91. It had earlier hit a three-month high due to expectations of a Federal Reserve rate hike this year.
S&P 500 e-minis were up 2.75 points, or 0.13 percent, with 56,774 contracts traded at 8:37 a.m. ET (1237 GMT).
Nasdaq 100 e-minis were up 13.25 points, or 0.28 percent, on volume of 11,928 contracts while Dow e-minis were up 37 points, or 0.21 percent, with 9,069 contracts changing hands.
Investor sentiment was also buoyed by positive signals from Greece. Greek banks reopened their branches across the country after a three-week shutdown.
Morgan Stanley shares were up 1.5 percent to $40.80 in premarket trading after the U.S. bank's consolidates net revenue rose 13 percent.
PayPal Holdings was up 3.8 percent to $39.85 on a "when-issued" basis premarket ahead of its trading debut after it split from e-commerce company eBay.
Vivint Solar soared 42.4 percent to $15.58 after solar company SunEdison said it would buy the company in a deal valued at about $2.2 billion, including debt. SunEdison was up 3.3 percent to $32.59.
Horizon Pharma jumped 9.2 percent to $40.49 and was set to open at a record, after the Irish drugmaker raised its full-year sales forecast. (Reporting by Tanya Agrawal; Editing by Don Sebastian)