Nvidia is in advanced negotiations to kick money into PsiQuantum's current founding round, according to reports.

PsiQuantum is in the middle of raising capital, with Reuters previously reporting the Californian startup is targeting "at least" US$750 million ($1.17 billion) at a US$6 billion valuation.

PsiQuantum is building the world's first commercially-viable quantum computer in Brisbane thanks to a $940 million investment from the Commonwealth and Queensland governments.

Though many say such a machine is at least seven years away, PsiQuantum says it will have its supercomputer running by the end of 2027. A second will follow in Chicago.

An investment from Nvidia would be an about-turn of sorts, with CEO Jensen Huang earlier this year causing a slump among listed quantum companies after he said the tech is still about two decades away from maturation.

Huang walked that back in March when he hosted a gang of industry executives at an Nvidia "Quantum Day." Among those who joined Huang on stage was PsiQuantum founder Pete Shadbolt, who Huang joked already looked like "a builder from Australia".

Shadbolt told Capital Brief last year that the startup would need to raise more money, beyond the $940 million from the Australian governments, before it finishes its Brisbane computer.

Then-Industry Minister Ed Husic, who championed the PsiQuantum deal, told Capital Brief in March that PsiQuantum was raising money at a valuation that would prove the wisdom of the governments' investment.