Which distribution should I use based on my cpu's arch?

[Hongsheng Zhao <zhaohscas@yahoo.com.cn>]

Hi all

I've two computers and the cpu's informations are as follows:

Intel (R) Core (TM) i7 CPU 920 @ 2.67 GHz

and

Intel (R) Core (TM) 2 Quad CPU Q8300 @ 2.5 GHz

I want to know Which arch-specific distributions should I use based on
my cpu's arch listed above, especially, i386, ia64, or amd64?

Besides, I've found that the ia64 distribution only have one DVD, why?
Regards.

-- 
Hongsheng Zhao <zhaohscas@yahoo.com.cn> 
School of Physics and Electrical Information Science, 
Ningxia University, Yinchuan 750021, China
GnuPG DSA: 0xD108493
2011-3-15