I have install rhel 5 on my laptop
While on first boot it gave me following error

Memory for crash kernel (0x0 to 0x0) not within permissible range
PCI: Cannot allocate resource region 1 of bridge 0000:00:0c.0
PCI: Cannot allocate resource region 2 of bridge 0000:00:0c.0
PCI: Cannot allocate resource region 3 of bridge 0000:00:0c.0
ACPI: Getting cpuindex for acpiid 0x2
ACPI: Getting cpuindex for acpiid 0x3
Red hat nash Version 5.1.19.6 starting
Unable to access resume device ( /dev/sda7)
mount: Could not find the filesystem '/dev/root'
setuproot : moving /dev/ failed : No such file or directory
setuproot : error mounting /proc : No such file or directory
setuproot : error mounting /sys : No such file or directory
switchroot: mount failed : No such file or directory
kernel panic - not sysncing: Attempted to kill init


Any idea how to solve this problem.

Processor information
Amd Athlon 64-bit

Looks like the install was botched someplace.
Since RHEL is a commercial distro, your first port of call is the commercial support that you paid for. If you do not want commercial support then you should use a non-commercial distro.

The errors look more like the system is trying to recover from a crash. First it finds that the crash image has zero size, which is not right, and then it cannot find the swap partition. So this is probably not the very first boot. Which laptop is this?

If you boot from the install media and enter "linux rescue" at the boot: prompt, we can have a go figuring out what happened.

fdisk -l will tell us you disk layout.

You want locate the root, swap and boot partitions (if you used the default). In the boot partition, you need to locate and show us the grub.conf file. In the root partition you need to locate and show us the fstab file. The entries in these will be compared with the fdisk -l output so you'll need to provide that two.

Ask questions about anything that isn't clear.

Find the grub.conf ,fatab ,fdisk -l output

default=0
timeout=5
splashimage=(hd0,2)/grub/splash.xpm.gz
hiddenmenu
title Red Hat Enterprise Linux Server (2.6.18-53.el5)
root (hd0,2)
kernel /vmlinuz-2.6.18-53.el5 ro root=LABEL=/ rhgb quiet
initrd /initrd-2.6.18-53.el5.img
title Other
rootnoverify (hd0,0)
chainloader +1


LABEL=/ / ext3 defaults 1 1
LABEL=/usr /usr ext3 defaults 1 2
LABEL=/boot /boot ext3 defaults 1 2
tmpfs /dev/shm tmpfs defaults 0 0
devpts /dev/pts devpts gid=5,mode=620 0 0
sysfs /sys sysfs defaults 0 0
proc /proc proc defaults 0 0
/dev/sda7 swap swap defaults 0 0


Disk /dev/sda: 160.0 GB, 160041885696 bytes
255 heads, 63 sectors/track, 19457 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/sda1 * 1 2611 20971520 7 HPFS/NTFS
Partition 1 does not end on cylinder boundary.
/dev/sda2 2611 7833 41943040 7 HPFS/NTFS
Partition 2 does not end on cylinder boundary.
/dev/sda3 7834 7896 506047+ 83 Linux
/dev/sda4 7897 19457 92863732+ 5 Extended
/dev/sda5 7897 8940 8385898+ 83 Linux
/dev/sda6 8941 9723 6289416 83 Linux
/dev/sda7 9724 9984 2096451 82 Linux swap / Solaris

Disk /dev/sdb: 4102 MB, 4102028288 bytes
33 heads, 63 sectors/track, 3853 cylinders
Units = cylinders of 2079 * 512 = 1064448 bytes

Device Boot Start End Blocks Id System
/dev/sdb1 1 3854 4005871 b W95 FAT32



Laptop info

LAPTOP make : ACER Aspire 4520
Processor : AMD Athlon 64 bit
Storage : 160 GB sata

Right, lets make some things explicit.
You have three linux partitions, not counting swap.

sda3 = /boot (I hope)
sda5 = /
sda6 = /usr

guessing... but edit fstab. Where it says the LABEL=/ put /dev/sda5, where it says LABEL=/usr put /dev/sda6 and so on, for whichever is the right way around. Reboot.

I am getting the same error

So what did you do?
I left the specifics up to you, you realize this don't you?
How did you identify the correct partitions?