Place your bets .....

[#1]

Just upgraded the stepson's PC from an old AMD processor (4850e) to a newer Athlon II X3 445 (around 3 times the speed) plus moved him over from 2Gb DDR2 to 4GB DDR3
How long from when he start using it until he notices and how long before he thinks to thank me .......
Now lets hope my 8 core CPU turns up soon or I will have to suffer with a CPU-less Workshop machine until I spot another bargain .....

[#2]

Almost instantly
Depends if he is a teenager or adult ====> hard call to make

[#3]

Quote from: DomS

...how long before he thinks to thank me .......

If he's a typical youngster then it depends whether you consider a couple of weeks of stopping moaning about how rubbish his PC is qualifies as 'thanks'.

[#4]

He's just turned 16. I thought the X3 445 was a bit quicker than it was but it is still a 50% improvement over what he had (plus the memory etc)
I ordered up a FX-8150 for £55 delivered this morning - hopefully it wasn't a pricing error by the retailer