Which CPU and graphics card for Oblivion and HDTV?

[smekoslav]

I want a computer with CPU and graphics card that would easily play newest and most demanding games like Elder Scrolls IV: Oblivion and HDTV up to 1080p!

I was looking at these CPUs:
PENTIUM D 920, 2,800GHz 2×2MB, 800MHz, LGA775
AMD ATHLON 64 X2 3800+ BOX S939 DUAL CORE
PENTIUM 4 3,400 GHz 2MB 64bit 800MHz LGA775 BOX
Any other suggestions? Which one should I get?

And these were my GC choices:
Club 3D Ati Radeon X1900XT, 512MB, VIVO, PCI-e
Club 3D GeForce 7900GTX, 512MB, PCI-e
Which one is better?

How much RAM? Is 1GB enough?
How much power supply? 450W?
I would appreciate some advice regarding cooling too if it's necessary for any of these components.

 

[tweaker]

If you've got the money,
3800+
7900GTX
Preferably 2GB on RAM.

 

[smekoslav]

Why do you suggest GeForce over Radeon?
I've always used Radeon cards in my life and I was pretty satisfied, that's why I ask...

 

[tweaker]

Why do you suggest GeForce over Radeon?
I've always used Radeon cards in my life and I was pretty satisfied, that's why I ask...

Because the GTX would perform best out of the two listed. An X1900XTX would be a nice option though, if you've got the money, they perform very nice with oblivion.

 

[apj101]

I've always used Radeon cards in my life and I was pretty satisfied, that's why I ask...

if you've always used radeon how do you know geforce arnt better i'm not saying they are but just poking fun

 

[smekoslav]

So X1900XTX is better than GTX and X1900XT isn't?
What's so important difference between XT an XTX?

 

[smekoslav]

I'm kinda deciding to go with AMD 3800+ X2 and X1900XT, but which motherboard? Is it important or can I just get something like Gigabyte GA-K8N51 GMF, 939? Will be PSU 450W enough?

 

[ceewi1]

I'm kinda deciding to go with AMD 3800+ X2 and X1900XT,

Good choice. The higher price of the XTX isn't worth the money, IMO.

but which motherboard? Is it important or can I just get something like Gigabyte GA-K8N51 GMF, 939?

The Asus A8R-MVP is good, but it depends on your budget.

Will be PSU 450W enough?

Depends on the PSU, what's the amperage on the +12V rail? If it's a generic one, that comes with a cheap case, then no. If it's a quality one then yes.