Why Harry Potter cannot be set in 1991-?

[sebfish5]

No: HPFGUIDX 79226

This has probably been mentioned before but I have seen no sign of 
it. Harry Potter, as worked out by the fans, is set in 1991, due to 
the deathday cake. However, in book one (which I have leant, along 
with 2, to a unbeliever, so I cannot give exact quotations)
 
"You could let me stay in the house?" said harry hopefully, he could 
watch dudleys T.V and maybe have a go on dudleys playstation for 
change.

 In 1991, unless I am VERY much mistaken, being a videogame player, 
the playstation 1 was not around. Please correct me if I am wrong, 
but I am 99% sure that the playstation was not released six years 
before the N64, on may 1st 1997.

 If i am correct, then when is Harry Potter set, or has this 
argument been cleared up?


 Seb