Crucial Ballistix PC4000 - after memtest one stick dead

This is my old setup :
P4 3.2GHz @3.6 225FSB 1.575v
GA-8KNXP Rev1 Bios F13
Ballistix PC4000 512MBx2 @225MHz 2.5-3-3-8 2.8v
ATI 9600XT @default clock
Scythe Plug-in 430W ATX2.1 14cm fan PSU
3x200Gb Maxtor SATA
Audigy 2 ZS Platinum
TT Bigwater SE + Coolermaster NB&GPU block

Before this,I ran my CPU with default speed and RAM 200MHz 2-2-2-5 2.55v.
After fine tune my memory and cpu setting, ran memtest without error.But the problem is after finish memtest and reboot, my system wont post.MB keeps giving me beeps sound so I reset my BIOS but still couldnt post and got that beeps.

Pull out one of the RAM stick and test each one and I found one of them couldnt post.Is it dead?What is the problem?Still I can get my lifetime warranty?
And s*/t now I am studying in japan so no nearby support here.Wish that this system could live for more 1~2 years.