I wouldn't, if your going to go AMD i would not get a 754Pin AMD64 motherboard.
Just to fill you in, there are two different types of AMD64 motherboards:
AMD64 Motherboard (754Pin) & AMD64 Motherboard (939Pin)
754Pin was the first 64Bit released by AMD, so it was a stepping stone in terms of 64Bit technology, it was actually released quite awhile back, however the price was very high and so people generally were sticking with the AthlonXP (mainly the Barton) due to its overclocking ability.
Over the last few months AMD have released a new set of motherboards (the 2nd stepping stone if you like) called 939Pin, 939Pin is called 939 because the CPU on the AMD64(939) boards use nine hundred and thirty nine pins.
The 939Pin performs between 5-10% faster than the 754Pin motherboards...
I hear you shouting.. "Whats the point in spending the extra £50-£100 on getting a 5-10% performance increase!?"
Well.. it's not only that but AMD has stopped the line of 754Pin processors (not from being manufactured) but in development form. This means the highest processor that you will be able to get for 754Pin motherboards is the AMD64 3400+, which i think you'll agree will be a waste of an upgrade if you cannot upgrade your cpu any further..
Plus 939 has new boards being released over the next month that support SLI and PCIe (PCIe = faster than AGP & SLI = 1.8x speed of 1 graphics card, meaning you can run 2xSameCard and it will perform 1.8x that of having 1 of them as it will utilize both of them at the same time (Dual GPU's).
So spending the extra cash is worth while, however if you are going to cut back on something in your new system i would not cut back on the motherboard or CPU, get the best u can of these, use 256mb - 512mb memory if you must (512mb being average to use).
There really is no point in buying anything below a 3200+ speed AMD64 cpu, if you do not want to upgrade soon, as the 2800+ and 3000+ 939 Winchester 64bit CPU's are equal in most things if not beaten by an overclocked AMD Barton Mobile chip (1.4V Vcore) (reaching 2.5-2.7Ghz air cooled)
I personally would get:
AMD64 3200+ Winchester (939) £140
MSI Neo2 Platinum with SLI and PCIe Nforce4 £120-£150