Processors vs Memory

If I have a fixed amount of money to spend as a general rule is it better to buy one processor and lots of memory or
twoprocessors and less memory for a system which is transactional based (in this case it's handling reservations).  I
realisethe answer will be a generalised one but all the performance bits I've read seem to talk about adjusting memory
allocation. The client has received the general advice from their hardware supplier that 2 Xeon processors and less
memoryis better but for postgresql I'm thinking they might be better off with a single processor and loads of memory.
TheOS is Red Hat Linux. 

How long is a piece of string  I guess but all comments welcome!

TAI
Hilary


Hilary Forbes
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