Hum
Shuttle = higher price.
A s/h P2 450 can be bought for £60 nowadays....
(i ran one just for that)
Alternatively you could buy a new cheap `all in one` motherboard with built in graphics and sound etc for less than £40, and fit that into an old 486 case...using the old HD etc.
[ you will still have to buy a compatible power supply(£20) and memory(£20) though ]
