£300 What to Upgrade?

[PC-M Vip3r]

I'll have £300 ish to spend on upgrades over the next few weeks. My current Spec is:

CPU - Intel p4 3.00
MOBO - Asus P4S800D-X
GFX Card - nVidia GeForce FX5500 128MB
RAM - 1GB Value Ram (2x512)
HDD - 160GB IDE
PSU - Came with case 450W

I am wanting to upgrade to something A little Better for gaming. Im looking for some more Ram to support my web design applications. I also want a new case, something like the iCute (the one with the 140mm fan in the front).

Could you guys suggest what would be best to do?

TIA!

 

[PC-M Vip3r]

My CPU is overclocked to 3.3 Stable with a EVo 33 Cooler on it, But I would be looking for some more Speed. I have just found out that i will Have £400 to spend!