Help with a new system?

[Escalation12]

I've had a Pentium 4 @ 3.02GHz with 1GB of RAM for about the past 10 years now. It's handled pretty much everything I've wanted it to but now it's really showing it's age and I need something new.

My budget is £400-450 and I'd want this system for everyday browsing (multiple tabs/windows), some light Photoshopping (working with fairly small files) and general use. I don't play PC games at all as I have a console for that (sorry to the PC gamer enthusiasts! )

I also watch a ton of TV shows and movies daily, all at 720p/1080p but using DXVA, I let my current XFX Radeon 4650 handle the load so the CPU is kept my CPU entirely free (doesn't push past 20% usage while even the card's usage only bounces between 15-25% even on 20-40GB files).

I don't need a crazy good PC as you can tell because I don't do anything too intensive, but I want a solid system nonetheless. Can anyone help me out in that price range?

I don't require a monitor as I've got a fairly new one. Mouse/keyboard I'm OK with but may buy new later on. Sound card/speaker system also not necessary as I adore my current Santa Cruz Turtle Beach/Altec Lansing combo -- it'd be ideal if the new motherboard had a slot for my Santa Cruz PCI sound card.

Thanks in advance!

 

[Escalation12]

My apologies for not being more thorough in the first post I made - didn't think it through well enough at the time unfortunately.

My current primary HDD is an IDE one and I do also have a 1TB Samsung SpinPoint SATA drive installed in my current system but it's filled with TV shows/movies/backups so I would require a new one as my main drive for this new system (and I'd install the SpinPoint into it and continue to use as a storage drive like I have done up until now).

The new primary drive doesn't have to be big, even a SATA drive with 150-300GB capacity would be fine for me. I will need an ODD/PSU/case! OS is already covered.

Thanks again in advance.