It's a good comparison, but I do have to point out a few flaws.
The 9500GT has to have been included as a joke. Anything nVidia release below a x600 can only be perceived as a multimedia/desktop card (even tho ALL gfxcards promote themselves as "great gaming performer" - that's shtick). It's always been the case with the x400, x200 etc. Hence they're around or below £50. Now if u did a pureHD comparison also, that'd be different perhaps.
I have a 8400 in a media pc, and have no expectations of benching it against a 8600.
If u popped in a 9600GT, as nVidia's base expectation for proper game playing, then we could perhaps be more serious. The costing ofc would be that much different, but also would be the performance.
It is great that the 4830 can push it's elder brothers when it's oc'd, but what bothers me in the comparisons is that if u bought the brother - u'd most probably oc that too. Tricky.
For £100, I don't know about the validity of getting this card tbh. It's not something I'd promote.
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