The S&P 500 (^GSPC) flirted with all-time highs but ended the day nearly flat, just shy of its record level. Nvidia shares rose over 4% to end Wednesday's trading session above $154, notching a new record high.

US market opened higher for the fourth session on Thursday as well, with the Dow Jones Industrial Average advancing over 208 points or about 0.4%, just after the opening bell. The tech-heavy Nasdaq Composite increased 0.

Mixed messages from multiple sources continue to make for a messy market for investors, traders and speculators.