(Recasts with record closing high for S&P 500, adds market details, VIX milestone, volume data)
* IBM tumbles after missing quarterly revenue estimates
* Tesla trades higher after Q3 report
* Indexes: Dow down 0.03%, S&P up 0.30%, Nasdaq up 0.62%
* VIX volatility index hits lowest close since Feb. 2020
By Shreyashi Sanyal, Devik Jain and Sinéad Carew
Oct 21 (Reuters) - The S&P 500 boasted a record closing high and its seventh straight session of gains on Thursday while the Nasdaq was boosted by such high-profile stocks as Tesla Inc and Microsoft Corp but a tumble in IBM shares weighed on the Dow.
After hitting an intraday record the previous day the Dow was in the red for most of Thursday's session as IBM fell 9.6% after missing Wall Street estimates for quarterly revenue as orders in one business segment declined ahead of a spinoff next month.
Among the S&P's 11 major sectors, the biggest boost for the benchmark came from consumer discretionary stocks and the technology index, while energy stocks were the biggest drag as crude oil futures fell on concerns about demand.
"For the most part you're dealing with a slightly risk-off day with people going back to more defensive sectors" including big technology companies, said Chris Zaccarelli, chief investment officer at Independent Advisor Alliance in Charlotte, North Carolina.
"You're seeing oil down a little bit today so potentially there's some global growth concerns. You're seeing some inflation concerns as well."
However, the CBOE Volatility index, also referred to as Wall Street's fear gauge, closed at its lowest level since February 2020. Shortly after that date, the volatility index had climbed as COVID-19 brought the global economy its knees.
The VIX's low level implies that investors do not see a big decline or upswing for stocks ahead despite widespread concerns about supply-chain problems hiking costs, according to Shawn Cruz, senior market strategist at TD Ameritrade.
"The market may be saying the supply-chain issues that are driving up costs are going to be transitory because markets are discounting mechanisms," pricing in what investors expect to happen in the future, Cruz said.
The strategist also pointed to earlier data showing that the number of Americans filing new claims for unemployment benefits dropped to a 19-month low last week, suggesting a tightening labor market.
The Dow Jones Industrial Average fell 6.26 points, or 0.02%, to 35,603.08, the S&P 500 gained 13.59 points, or 0.30%, to 4,549.78 and the Nasdaq Composite added 94.02 points, or 0.62%, to 15,215.70.
Analysts were expecting S&P 500 third-quarter earnings to rise 33.7% year-on-year, with about 100 company reports in so far, according to the latest data from Refinitiv.
Tesla was the Nasdaq's biggest boost, rising more than 3%, as investors digested the electric car maker's upbeat earnings, despite a supply-chain warning.
American Airlines finished up 1.9% after the company posted a smaller-than-expected quarterly loss, while Southwest Airlines Co fell 1.6% after it said it expected current quarter profit to remain elusive.
HP Inc gained 6.9% as brokerages raised their price targets on the stock after the personal computer and printer maker forecast upbeat fiscal 2022 adjusted profit and raised its annual dividend.
Declining issues outnumbered advancing ones on the NYSE by a 1.22-to-1 ratio; on Nasdaq, a 1.00-to-1 ratio favored advancers.
The S&P 500 posted 60 new 52-week highs and no new lows; the Nasdaq Composite recorded 112 new highs and 37 new lows.
On U.S. exchanges 10.07 billion shares changed hands compared with the 20-day moving average of 10.27 billion. (Reporting by Shreyashi Sanyal and Devik Jain in Bengaluru, Sinéad Carew in New York Editing by Arun Koyyur and Matthew Lewis)