▸ US tech stocks exper­i­ence tur­bu­lent trad­ing amid valu­ation con­cerns

▸ Wor­ries per­sist des­pite optim­ism over Nvidia earn­ings as Vix fear gauge rises

▸ European stocks close higher, led by Ger­many’s Dax index

US tech stocks dropped yes­ter­day in tur­bu­lent trad­ing as optim­ism over Nvidia’s robust earn­ings was over­shad­owed by a fresh bout of fears over lofty valu­ations for arti­fi­cial intel­li­gence com­pan­ies.

The Nas­daq Com­pos­ite was down about 1.2 per cent in after­noon trad­ing in New York, giv­ing up a gain of more than 2 per cent. The S&P 500 was down

0.9 per cent.

Shares in Nvidia — seen as a bell­wether for the boom in arti­fi­cial intel­li­gence — had ini­tially ral­lied more than 5 per cent after the group pos­ted bet­ter than expec­ted quarterly res­ults late on Wed­nes­day, but slumped 1.1 per cent later in the ses­sion.

The Vix index, Wall Street’s so-called fear gauge, soared from about 20 to 28 in the course of two hours, a sharp move that under­scored the abrupt bout of volat­il­ity that jol­ted US equit­ies mar­kets.