Get an Athlon 64 3200+ Winchester 90nm chip, plenty fast enough for FFDshow and Hidef stuff and a bargain at £125 http://www.ebuyer.com/customer/prod...2hvd19wcm9kdWN0X292ZXJ2aWV3&product_uid=83377
. For the motherboard it depends whether you want to go PCI express or not. I did originally and had all sorts of problems so went back to AGP, I think seeing as AGP is perfectly good enough for HTPC duties and is more tried and tested I'd be tempted to go for that. The Asus A8V deluxe is very good (that's what I'm using) , costs about £80 but it's feature packed and stable. Another thing to consider with the mboard is if you are going to fit a non standard CPU heatsink/fan e.g. Zalman 7000cu. It's possible but how easy depends on how the standard backplate is attached to the motherboard. In the case of the Asus A8V it's glued on and I had to get a hairdryer to it to heat up the glue in order to be able to remove the backplate and replace it with the one you need for the Zalman cooler. It's a scary proposition but in my case it all worked out fine, just something to bear in mind! If you're happy to use the standard AMD heatsink/fan this isn't an issue at the expense of some decibels..... As for the graphics card, if you've got the AGP route for the motherboard then just something like a Radeon 9600 non pro will be fine, seems to be working well in my setup. For PCI express then a Radeon X600 perhaps, if you want a good all round card i.e. very good for games as well as HTPC duties then an Nvidia 6600GT is a good bet, about £150 though but it's about as good as it gets at the moment for HTPC duties to be honest. As for a soundcard, you may well find you don't need one, at least to start with. I'm not using one at the moment and am perfectly happy with the sound, just use the SPDIF output on the motherboard and send the output to your amp. I'd do that to start with and if you find you can't live with it add a soundcard later. DVD burner, NEC 3520A is good, Plextor 716A is very nice and very short but expensive! Do you need any video capture capability, if so analogue (e.g. from Sky box) or Digital Freeview? Choice of capture card is dictated a lot by what OS you are going to use, with WinXP Pro you have a choice of e.g. Sweetspot for analogue capture or the Nebula DVB card for freeview reception. If you use Win MCE 2005 (I think MCE 2005 is excellent personally) then the black gold cards are the best Freeview option or something like a Hauppage PVR-150MCE for analogue capture from e.g. Sky.
Hope that helps , I know what it's like, I changed my spec I don't know how many times before I settled on what I have now and so far it's working very very well.. in case you're interested this is what I went for:-
Claritas 390A case
Silenx 280W matx PSU
Athlon 64 3200 Winchester (Cooled by Zalman 7000Cu)
Asus A8V Deluxe Motherboard
Radeon 9600 Graphics card
Geil 1GB Dual Channel Ram
Plextor 716A DVD Burner
Hauppage PVR-150MCE (from Gigtek)
Seagate Barracuda 160GB HD
Win MCE 2005
Gyration Ultra Keyboard/Mouse
Theatertek 2 installed and thoroughly recommended!
The above combination is VERY quiet (the HD is the loudest component!). If you're interested I'll take some pics later of it in operation showing what MCE 2005 is all about and how it looks once set up....