Jan 19 (Reuters) - Retail investors were less enthusiastic about buying the dip in U.S. stocks on Tuesday, the latest sign of a possible fatigue after last year"s tech-fueled trading frenzy, Vanda Research analysts said in a weekly note. Individual investors bought $1.6 billion in stocks on Tuesday when U.S. shares sold off sharply after weak results from Goldman Sachs (GS.N) and a spike in U.S. bond yields. By contrast, they had bought close to $2 billion on Sept. 28 when the S&P 500 fell 2%. "Retail investors bought a lot less than they typically would," Vanda"s Ben Onatibia and Giacomo Pierantoni said about Tuesday"s session. "This could be the first sign that retail fatigue or capitulation is setting in, at least in the tech space." Vanda"s research note comes as enthusiasm around so-called "meme stocks" also appears to be fading, a year on from the GameStop Corp (GME.N) frenzy when retail investors coordinated on online message boards to buy into heavily shorted stocks. A report on Friday showed young investors were losing interest in these "meme stocks", with Gen Z"s attention shifting to companies in areas like electric vehicles and the "metaverse". read more A large share of purchases on Tuesday was concentrated in ProShares UltraPro QQQ (TQQQ.O), a leveraged ETF that targets three times the one-day return on the Nasdaq 100 Index (.NDX), helping cushion the blow from the massive institutional selling in the sector, Vanda"s analysts said. Even Microsoft Corp"s (MSFT.O) bumper $68.7 billion purchase of "Call of Duty" maker Activision Blizzard (ATVI.O), the biggest gaming industry deal in history, failed to cheer up retail investors. read more Retail investors were net sellers of Activision on a day when its shares jumped 26%, the research house said. Buying in retail favorites, including Tesla Inc (TSLA.O), Apple Inc (AAPL.O), Advanced Micro Devices Inc (AMD.O) and Nvidia Corp (NVDA.O), has also diminished amid a tech sell-off that started last month, according to Vanda Research.