** A sub-index of Australian tech stocks .AXIJ rises as much as 5.2%, set for its best day since early April, if trend holds
** The sub-index rises after Nvidia NVDA.O gained more than 5% in extended trading session as the artificial intelligence leader forecast fourth-quarter revenue above Wall Street estimates
** Data centre operator NEXTDC NXT.AX rises as much as 8.1% and accounting software maker Xero XRO.AX gains 5.8%
** WiseTech Global WTC.AX climbs 5.1%, while enterprise software co TechnologyOne TNE.AX adds 7.4%
** AXIJ down 15.4% YTD, including day's move, vs a 4.6% gain in benchmark index .AXJO
(Reporting by Himanshi Akhand in Bengaluru)
((Himanshi.Akhand@thomsonreuters.com;))