affected 32 bits register

From: delicious (kjwdelicious_at_empas.com)
Date: 03/19/05 

Date: Sat, 19 Mar 2005 23:59:16 +0900

Hey guys...
I got a problem
Actually I think I found something very curious.
A 32bit register can be affected by changing other 32bit register
or a high 16bits of 32bit register also can be affected by changing low
16bits.

Please look at this code.
mov eax, 0FFFFFFFFh ;set all bits
mov ebx, 0FFFF0000h

I looked into these step by step through CV debuger.
And I found eax value changed from 0FFFFFFFFh to 0000FFFFh when mov ebx,
0FFFF0000h.
And I found that other 32bits registers also affect to others, each other.

So, can't I change low bits of EAX(AX part) without changing high bits of
EAX?
I'm serious... Please let me know why...

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