Asus V9900 FX5800 - Question

We got our new system last week and we're very pleased with it. The
graphics card is an Asus V9900 FX5800, Mobo an ASUS A7N8X Deluxe, 1Gb RAM
and running Win2000 professional.

When chatting with the engineer who built the computer for me he was telling
me that the graphics card has a fan which kicks in only when required. He
mentioned that its noise can be quite noticeable so that we would not be
suprised by it.

However my son (who uses the machine most often) says that so far he's never
actually heard it. Perhaps theres nothing wrong at all but just wanted other
peoples opinions...

I guess there are a number of possibilities,

1) Perhaps we haven't thrown anything difficult enough at the graphics card.
My son has been playing Enter The Matrix and GTA vice City at high
resolution and graphic levels etc and has also run tests called "3D Mark
03". These all look good but the fan does not kick in.

2) Perhaps we haven't got the Driver software or the games set up properly?

3) Could there actually be a hardware problem preventing optimum
performance?

What do people think?

Kath