A clinical first half display saw in-form James (2), Cory Allen, Josh Navidi and Dan Fish all grab tries as the hosts wrapped up the desired bonus point inside 25 minutes.
The tries continued to flow after the break as James completed his hat-trick, Allen went over again and Ethan Lewis – a first senior try – and Alex Cuthbert, Aled Summerhill, Rhys Patchell and Macauley Cook all crossed the whitewash.
The result ultimately proved in vain as Montpellier’s win over Harlequins ensured Cardiff Blues could not make it through the pool stages.
However, Head Coach Danny Wilson will have be thrilled by the manner of victory as his team built crucial momentum before a return to Guinness PRO12 action next weekend at home to Edinburgh Rugby.
The home side were quickly into their flow against the Italians and early pressure paid off as the forwards took the ball on and fed it wide to James to crash over in the corner. Gareth Anscombe’s touchline conversion meant it was 7-0 after six minutes.
A second try followed within minutes as Josh Navidi charged up field, Dillon Lewis carried ball on and, after Cuthbert broke the rearguard, it was Gavin Evans who provided the final pass for Allen to race down the touchline to score.
The Italians responded with a penalty from fly half Florin Vlaicu, after a scrum penalty. But it was no more than a blip as Allen floated a superb pass out to James to tear over for his second of the night.
The forwards looked hungry for ball with young tighthead Lewis and Lou Reed crashing into contact before Fish showed his growing confidence with a sublime kick in behind.
Fit-again Sam Warburton produced a massive boot up field after lost visiting lineout before the bonus point arrived on 25 minutes as Number Eight Navidi touched down at the back of a rolling maul.
Cam Dolan showed his appetite for the game with a big shunt up the left wing before a quick tap and go from the ever alert Tavis Knoyle saw him kick in behind and the ball sat up perfectly for Fish to gobble up the ball in full flow and go over for a 33-3 lead at the break.
Cuthbert thought he was away after a loose ball was hacked forward at the start of the second half, but a superb last ditch tackle saw him hauled down metres short of the line.
But it was only a temporary reprieve as Cardiff Blues did score on 50 minutes when a lineout was knocked back by Calvisano only to Ethan Lewis to gleefully pick it up and dot down for his first senior try.
James scored his hat-trick with one of the game’s highlights when on halfway he burst past his man on the outside and then cut in field to beat three man for pace for a superb solo effort.
Then Allen picked off a pass for an intercept score and the half century was rattled up on the hour.
The attacking rugby continued as replacement Scott Andrews broke the line and Warburton burst down the middle on shoulder before a perfectly delayed pass from Anscombe sent Cuthbert into space and over for a ninth home try.
The tenth try arrived after brilliant work from Ellis Jenkins at the breakdown secured ball. A tap and go from Williams saw him link with Dolan before he fed Summerhill to cruise in.
The home side did not even let up in the final minutes as Patchell broke down the right before the final play saw Cook at the end of more neat team play to finish a convincing performance.
06m James t Anscombe c 7-0
09m Allen t Anscombe c 14-0
13m Vlaicu p 14-3
16m James t Anscombe c 21-3
25m Navidi t Anscombe c 28-3
30m Fish t 33-3
50m E Lewis t 38-3
52m James t 43-3
56m Allen t Anscombe c 50-3
61m Vlaicu p 50-6
64m Cuthbert t Anscombe c 57-6
74m Summerhill t 62-6
77m Patchell t Anscombe c 69-6
80m Cook t 74-6
Cardiff Blues: 15 Dan Fish (Patchell 62), 14 Alex Cuthbert, 13 Cory Allen, 12 Gavin Evans, 11 Tom James (Summerhill 56), 10 Gareth Anscombe, 9 Tavis Knoyle (Williams 73); 1 Gethin Jenkins (Davies 62), 2 Ethan Lewis (Rees 66), 3 Dillon Lewis (Andrews 59), 4 Jarrod Hoeata (Cook 65), 5 Lou Reed, 6 Cam Dolan, 7 Sam Warburton, 8 Josh Navidi (E Jenkins 54)
Replacements: 16 Matthew Rees, 17 Thomas Davies, 18 Scott Andrews, 19 Macauley Cook, 20 Ellis Jenkins, 21 Lloyd Williams, 22 Rhys Patchell, 23 Aled Summerhill