[def4d]

You can have a 1To 32Mo HD for ~100- 120 euros (or 2x500Go)
You could always buy a bigger proc than the Q6600, but i think it's still today the more interesting in term of price/speed (including motherboard and ram)

[tanguy]

Hi, i like to add some infos...
First, HD doesn't impact on the render time itself, TRUE, but it impact on all the side process like Merging MXI, loading large Textures before the Rendering Processing. So, i thing, it s my point of view... Rendering Process isn't only a CPU question, and it's true for quite all the different Render engine.

And for the HD, be very careful about the huge HD. HD manufacturers can't give you the assurance of a good functioning of the huge one, over 160GB... So keep this in mind. And if it's only for rendering, prefer definitively more RAM ( good one by the way) than HD.
A render node just need a fast CPU, at least 2 gig per core and a 1Gb LAN chipset.

So, i finish !

Tanguy