HTPC hardware recommendations

I'm currently running an old Power Mac G4 as an HTPC. While it does a fine job for SD video files of TV shows, anime, etc, and a fine job for DVDISO/VIDEO_TS folders, I'm toying with the idea of either upgrading or putting together a whole new system to connect to the TV for theatre purposes.

I had a few questions about this, hardware-wise.

First of all, would a Sonnet Encore Duet dual-proc 1.8GHz G4 upgrade have the oomph to play back 1080i/1080p content? The current proc (single-proc 867MHz G4) can just barely handle 720p. If a CPU upgrade can enable the Mac to do 1080i/p playback then I might go that route.

However, the CPU upgrade in question is $600. I was looking at parts on NewEgg and I can assemble a whole new PC for just a little more than that. What I'm not sure of is which CPU and video device I should be using.

My initial choices were an AMD Athlon64 X2 5000 at 2.6GHz and an Nvidia GeForce 8600GT, as I remember reading that the 8600GT has MPEG4 acceleration that helps HD playback.

A few notable things about this:
-I'm generally not a fan of Intel. Call it geek politics, but I still think of the MS Windows + Intel hegemony and manufacturers always leaving AMD with their then-better chips out in the cold. If current Intel offerings are truly light-years ahead of what AMD has to offer, then that's fine and I'll consider a C2D or something instead. I'm bitter but not bitter enough to shoot myself in the foot

-This won't be used for (much) gaming or video encoding. I have a Power Mac G5 Quad for video gruntwork, and it does a lovely job of tear-assing through any video file I throw at it. I'm not worried about having to do much beyond smooth playback on the HTPC.

-That said, I would really like to be able to play back even 1080p with no dropped frames or stuttering. I don't know if the Athlon64 X2 + 8600GT is sufficient, insufficient, total overkill, whatever for that purpose.

-Also, it is going to involve the use of a DV-->HDMI adapter. I can't imagine any video cards having a problem with this, but I know some ATI cards have problems with DVI-->component due to a sync-on-green issue that I still don't quite fully understand. Again, probably not a problem, but I like to cover all my bases.

-Also also, motherboards. Does it really matter which one I get? What are points to consider when picking one for an HTPC, aside from plenty of IDE and SATA ports for lots of storage?

-Also also also, memory. How much/what kind is needed for HTPC purposes?

Thanks much, guys. I do appreciate it.

Jam it back in, in the dark.

AMD should work fine. However, Intel is receiving some price drops this/next week, so Intel looks attractive. But, if you're not planning to do any encoding and only using it as player, then you could go even lower. AMD X2 3800 is a good cheap option. (Intel was light years ahead for the last year, performance wise. However, we're waiting to see what AMD has in its hands and hopefully it won't be like the Radeon 2900).

There's one rule with mobos: Don't get a shitty one. Don't cop out and buy a cheap no-name brand. You'll never know that it'll fry your other components.

RAM: I'll say 1GB. It's a nice place to start and video playback isn't RAM intensive. However, prices are dropping slowly enough that even 2 GB of ram doesn't seem like a bad investments.

Other question, no clue.

There's nowhere I can't reach.

Cool, thanks.

As mobos go, I try to stick to the well-established names. ASUS, ABIT, Gigabyte, DFI. I've had bad experiences with MSI so I tend to shun their products.

Wow, I didn't know I could go as low as a 3800. I think my logic was that since I was unsure about the video card, I wanted to get a beefy processor in case the video card didn't wind up cutting the mustard.

Also good to know that I don't need the extra gig of RAM. I know RAM's cheap, but with something like this I want to have lots of money to pour into lots of storage considering that HD videos are HUEG LIEK XBOX.

Oh, what about onboard sound? Is it crap, is it good, is it okay but worth it to get a dedicated sound card anyway?

EDIT: Also, RAID. Good for something like this, or a waste of time/money? I'd be doing striping for the read/write performance boost. Mirroring isn't that important considering that when it all comes down to it, it's just a bunch of pirated movies.

This thing is sticky, and I don't like it. I don't appreciate it.

I know almost nothing but HTPCs, but I can answer some of your questions:

Intel vs AMD: C2D is better than AMDs current offerings because they are not only faster, but much more efficient. This means they use less power and run cooler, allowing for quieter CPU cooling (you can even get away with passive). Less power consumption also means less powerful PSU, which generally means less heat output. Less net heat in system = especially good for HTPCs since it means less noise.

RAID: There won't be much point in RAID 0 for you in my opinion. I would think you would want RAID 1 since it would be a pain in the ass to download all of your media again. If you get a motherboard with Matrix RAID (only available on Intel chipsets), you can split up your drives into RAID 0 and RAID1.

Sound: On-board sucks. You should at least get a cheap card such as the Chaintech AV-710, or if you have good speakers or are more discerning, an even better card. I can't recommend any better cards, though, because I don't know anything about them.

I am a dolphin, do you want me on your body?

C2D still use more electricity at the low end. They may have better performance per watt.. I'm looking toward lower power and lower consumption, which AMD is stronger in. I see no point in using C2D for a budge HTPC. X2 3800 is the bare minimum though. AMD's processors are dirt cheap. I think X2 5000 is like around $125.

If it's going to be an HTPC, might as well shell some money out for a decent soundcard and stereo system. Of course, if you don't really care too much, onboard sound should be fine. It all depends if you can hear the difference.

If you don't care about your files, RAID isn't important.

For what it seems like you're going to be doing, you can go with lower end parts. You're just looking for smooth playback, which doesn't requiring process heavy lifting. For example, look at HP: http://www.shopping.hp.com/webapp/sh...dec&catLevel=2
http://www.shopping.hp.com/webapp/sh...nter&aoid=1024

It's all pretty low end stuff. Pentuim D is present on one, which is pretty questionable. nVIDIA 7600, which isn't smoking hot. The other has x2 5000 and a nVIDIA 7300. I'm guessing you could go with a AMD processor around 4000 and even a GeForce 8300 to 8500. A HTPC isn't supposed to be high tech stuff.

I was speaking idiomatically.