Retail investors were buyers during much of the recent rollercoaster in U.S. stock markets, taking advantage of a sharp fall in popular tech shares, according to various research reports, although they also showed signs of caution.

While individual investors may have been swept up in the giant global stock market selloff on Monday triggered by a wave of anxiety about economic data and earnings news and exacerbated by the unwind of yen-funded trades, many continued to buy even as indexes plunged anywhere from 2.6% to 3.4% in heavy trading.

Vanda Research, a New York-based market research and analysis firm, found that individual investors caught up in the market storm remained net buyers of shares of companies like Nvidia, Intel and Advanced Micro Devices . They also directed more buying to an exchange-traded fund tracking 20-year Treasury bonds.

"There was no retail capitulation," said Marco Iachini, senior vice president of research at Vanda, who said the data captures the activity of self-directed individual investors -- those who don't turn to a big brokerage firm, financial adviser or private bank to handle their trading activity.

"Retail investors continue in their dip-buying spree," Iachini said.

Robinhood Markets received $1 billion of new cash from retail investor clients in the first week of August, a spokesman said, citing data provided by the company's founder, Vladimir Tenev. Of that, $500 million was deposited to client accounts during Monday's selloff, he said, compared with a second-quarter daily average of less than $350 million.

However, the firm's clients were unable to execute orders on Robinhood during overnight sessions, as Blue Ocean ATS, which executes those trades, couldn't handle the "extreme demand" from clients, Trenev told analysts on Robinhood's earnings call on Thursday.

Blue Ocean didn't respond to requests for comment.

A separate report published by analysts at JP Morgan said that retail investors were "aggressive net sellers" on Monday, with most of the selling pressure hitting the market in the first hour of trading. The bank didn't respond to requests for comment.

Both Vanda and JPMorgan said retail investors were resolute buyers during the market's recovery on Tuesday and Wednesday. But Vanda noted on Thursday that retail investors' interest in the iShares 20+ Year Treasury Bond ETF soared during the recovery, making the ETF the second-most-actively purchased security after Nvidia shares by Thursday morning.

Iachini said that may indicate "mom-and-pop-traders" are growing more anxious about the outlook for stocks and looking for a safe haven for some of their holdings.

Alight Solutions, which tracks trading activity in some 2 million 401(k) retirement accounts, found that those investors it tracks were actively moving assets out of stock funds and into money markets and fixed-income products, said Rob Austin, head of research at the firm.

"Trading was about eight times average," Austin said, although still small in absolute terms, with only 0.1% of the $200 billion in assets the firm tracks shifted from one investment strategy to another.

(Reporting by Suzanne McGee; editing by Megan Davies and Leslie Adler)