Shops that test CPU/mobo in London?

Are there any shops that test the CPU or Mobo to see if they are borked or not? Preferably cheaps ones! Thanks

P.S. The problem is that my old P4 rig doesn't POST anymore (all fans hdd etc are working) and I can hear the mobo constantly restarting the pc so I'm guessing its the cpu but I've had mobo problems before...

Have you tried replacing the bios battery on the mobo as it could be something as simple as that, if it's gone it won't hold bios info....only about £3 to buy from say a jeweller. :)

Nope I haven't but do batteries die after 1 year?

More like 3-5 years at least I heard...