I covered this in this thread
http://forums.overclockers.co.uk/showthread.php?s=&threadid=115729 . I don't claim to be an expert on OC UK but I've been a customer since the day it opened.
It was originally called Millennium Computers and Pete got a batch of Celeron 300 chips in. It was discovered that these chips would go at least 450 mhz and so the business began. Pete then moved a few units up into a bigger unit and Spie joined him on the internet side and so Overclockers was born. Thats how I remember it happening and I was in the shop every other day. Pete has now moved on.
When Millennium started (spelt wrong on purpose) it was just Pete, his wife and Dad. They then had a few helpers and some were hopeless. During the Celeron 300 days they had one staff member who new his stuff and he's the only surviving member. I have a really bad memory for names but he normally sits on the 2nd desk to the right. I'm sure he's a contributor on the forums so perhaps he'll reply. Anyway, Spie's internet side took off and he bought Pete out a few months ago and he looks like he's going from strength to strength.
Overclockers and Millenium Computers are now trading together under the holding company ESNET ltd (don't know what it means though).
In all the years that Millennium/Overclockers have been trading, Spie is a new boy really. From little acorns etc.
Heres an aerial picture of the 3 Millennium/Overclockers units.
Overclockers
1 - First Millennium shop
2 - Second Millennium Shop (Think it was changed to Overclockers while here)
3 - Overclockers now.
Lets hope somebody knows more.