CentOS: Unable to resume swap device SWAP-sda2

Last night, upgrade my AMD CPU to Intel CPU, everything works fine Ubuntu, but not able to boot Cent OS , with above error message .

Googled and got idea from http://fedoraforum.org/forum/printthread.php?t=120868



It seems vladak's message match to my case.
"I hit this problem while swapping motherboard+CPU (Athlon X2 instead of Sempron) for Fedora 10 box. After the hardware change (could be caused because the old motherboard had 2 IDE channels and the new one has only 1 ? the boot disk is connected via IDE.) the system reported the dreaded "Unable to access resume device" message. Booting from Fedora 10 install DVD into rescue mode, chroot to /mnt/sysimage and mkinitrd fixed the problem."

Fixed the problem with below steps.
1. Find the CentOS 5.5 install DVD and boot into rescue mode.
2. chroot /mnt/sysimage
3. cd /boot and move existing initrd*.img ./initrd_bak
[root@localhost boot]# ll initrd_bak
total 15648
-rw------- 1 root root 2663536 Aug 21 12:46 initrd-2.6.18-194.11.1.el5.img
-rw------- 1 root root 2663856 Aug 21 12:45 initrd-2.6.18-194.11.1.el5xen.img
-rw------- 1 root root 2663556 Sep 12 22:19 initrd-2.6.18-194.11.3.el5.img
-rw------- 1 root root 2663874 Sep 12 22:19 initrd-2.6.18-194.11.3.el5xen.img
-rw------- 1 root root 2663599 Sep 29 22:56 initrd-2.6.18-194.11.4.el5.img
-rw------- 1 root root 2663935 Sep 29 22:55 initrd-2.6.18-194.11.4.el5xen.img

4. invoke below command to initialize RAM disk

mkinitrd initrd-2.6.18-194.11.4.el5.img initrd-2.6.18-194.11.4.el5

5.  then I have below file, note tha the size is different with backup copy.
rw------- 1 root root 2672372 Nov 17  2010 initrd-2.6.18-194.11.4.el5.img

6. exit twice to boot up. cheers!