On Fri, 03 Aug 2007 08:54:03 -0700, iunknown
Kingston budget memory is usually a bad value, unless you
happened upon some with a rebate (often at a local store as
advertised in the newpaper).
Corsair has established itself as just as reliable, though
of course some variability arises when some particular
motherboard "X", may or may not be stable with memory "Y"
due to other factors than the brand. Factors like the
timings the modules use.
The other factor is random spot pricing from any particular
vendor, if the two above brands are same timings the
Kingston should not (would be unusual for it to) cost this
much more today.
You didn't mention specific models. Memory may cost more
due to being able to run at tighter timings which can
increase performance by (usually only) a minor %.
Forget the Vista benchmark. Benchmarks are only as
applicable as they are capable of reasonably reproducing the
environment where you need the performance. Running Vista
itself, you'd scarely notice the difference between 5400 or
6400 but in some more demanding application it may matter
more - so your benchmark should be more applicable to that
app. Even so if starting over to build a new system, 6400
seems more appropriate.
If you're willing to deal with a rebate and in the US, there
are more slightly cheaper and/or higher performing 6400
Regardless, since there can occasionally be compatibility
issues with any random motherboard (sometimes a bios update
helps, sometimes not) it is often best to buy from someplace
with a good return policy, and if the modules where instable
rather than only damaged in specific memory addresses, then
seeking a different brand/model instead of a replacement of
exact same thing again.