U probably get asked this a lot, but what version is my PS2?

[mart_is_good]

I am a newbie so please be patient...
I think it is a V3...

It is a UK PAL machine
It has 10 screws on the bottom
Its model number is: SCPH-30003
Its serial is: B 0 6 6 4 8 9 4
It has no pictures or stickers in the expansion bay.
I got it when it first came out in UK

Please can someone help me?

Also which chip is best, and where can you buy them?

Thanx