CentOS Development Server Crashing Frequently

I am running a development server on a fairly old version of CentOS 5. This server has been live almost constantly for the past five years ago, so has been pretty stable. A while ago, it crashed during normal operation. I restarted it and it crashed again after a few hours. The motherboard loading screen complained about CPU overheating. I opened up the box and cleaned out dust, and did indeed find a huge clump of dust clogging up the heatsink on the CPU. I also changed the RAM and, unfortunately, the RAM took a bit of a physical battering during this process.

The server continues to crash, but at different times:

• Once early during OS startup, just after the GRUB screen.
• Every time I log in and it tries to start the GUI, it crashes immediately.
• If I do not start the GUI, I can connect using SSH and use the server. It usually crashes after a few hours.
• It seems to crash quickly if I run yum updates.

I have investigated in the following ways:

CPU The crashes do not seem to be related to high server load, so far as I can tell. I have run top until it crashed and the server load seems low when it freezes.

RAM I ran memtest86+ for almost 9 hours and it said the RAM was fine.

HDD I ran badblocks on the two drives (they are in a RAID 1 array). The report came up entirely clean for both.

OS GRUB lets me select from 4 kernels. I have tried one of the alternatives and it made no difference.

LOG I am not experienced at looking through Linux logs. I have posted two outputs from dmesg below, each from just after a crash and reboot. Some of the messages in the log may relate to USB devices: there is a KVM switch which causes the keyboard and mouse to regularly connect and disconnect.

SO... I am thinking that I need to reinstall CentOS (I could move to a more recent version) and that this is not hardware related. I would appreciate the opinions of others, however.

[root@localhost ~]# dmesg
Linux version 2.6.18-308.20.1.el5 (mockbuild@builder10.centos.org) (gcc version 4.1.2 20080704 (Red Hat 4.1.2-52)) #1 SMP Tue Nov 13 10:16:17 EST 2012
BIOS-provided physical RAM map:
 BIOS-e820: 0000000000010000 - 000000000009fc00 (usable)
 BIOS-e820: 000000000009fc00 - 00000000000a0000 (reserved)
 BIOS-e820: 00000000000e4000 - 0000000000100000 (reserved)
 BIOS-e820: 0000000000100000 - 000000003ff30000 (usable)
 BIOS-e820: 000000003ff30000 - 000000003ff40000 (ACPI data)
 BIOS-e820: 000000003ff40000 - 000000003fff0000 (ACPI NVS)
 BIOS-e820: 000000003fff0000 - 0000000040000000 (reserved)
 BIOS-e820: 00000000fff80000 - 0000000100000000 (reserved)
127MB HIGHMEM available.
896MB LOWMEM available.
found SMP MP-table at 000ff780
Memory for crash kernel (0x0 to 0x0) notwithin permissible range
disabling kdump
Using x86 segment limits to approximate NX protection
On node 0 totalpages: 261936
  DMA zone: 4096 pages, LIFO batch:0
  Normal zone: 225280 pages, LIFO batch:31
  HighMem zone: 32560 pages, LIFO batch:7
DMI 2.3 present.
DMI: To Be Filled By O.E.M. To Be Filled By O.E.M./K8VSEDX, BIOS 1004.006 08/03/2004
Using APIC driver default
ACPI: RSDP (v000 ACPIAM                                ) @ 0x000fa8b0
ACPI: RSDT (v001 A M I  OEMRSDT  0x08000403 MSFT 0x00000097) @ 0x3ff30000
ACPI: FADT (v001 A M I  OEMFACP  0x08000403 MSFT 0x00000097) @ 0x3ff30200
ACPI: MADT (v001 A M I  OEMAPIC  0x08000403 MSFT 0x00000097) @ 0x3ff30390
ACPI: OEMB (v001 A M I  OEMBIOS  0x08000403 MSFT 0x00000097) @ 0x3ff40040
ACPI: DSDT (v001  A0058 A0058002 0x00000002 MSFT 0x0100000d) @ 0x00000000
ACPI: PM-Timer IO Port: 0x808
ACPI: Local APIC address 0xfee00000
ACPI: LAPIC (acpi_id[0x01] lapic_id[0x00] enabled)
Processor #0 15:12 APIC version 16
ACPI: IOAPIC (id[0x01] address[0xfec00000] gsi_base[0])
IOAPIC[0]: apic_id 1, version 3, address 0xfec00000, GSI 0-23
ACPI: INT_SRC_OVR (bus 0 bus_irq 0 global_irq 2 dfl dfl)
ACPI: IRQ0 used by override.
ACPI: IRQ2 used by override.
ACPI: IRQ9 used by override.
Enabling APIC mode:  Flat.  Using 1 I/O APICs
Using ACPI (MADT) for SMP configuration information
Allocating PCI resources starting at 50000000 (gap: 40000000:bff80000)
Detected 2202.999 MHz processor.
Built 1 zonelists.  Total pages: 261936
Kernel command line: ro root=/dev/VolGroup00/LogVol00 rhgb quiet
mapped APIC to ffffd000 (fee00000)
mapped IOAPIC to ffffc000 (fec00000)
Enabling fast FPU save and restore... done.
Enabling unmasked SIMD FPU exception support... done.
Initializing CPU#0
CPU 0 irqstacks, hard=c0774000 soft=c0754000
PID hash table entries: 4096 (order: 12, 16384 bytes)
Console: colour VGA+ 80x25
Dentry cache hash table entries: 131072 (order: 7, 524288 bytes)
Inode-cache hash table entries: 65536 (order: 6, 262144 bytes)
Memory: 1029916k/1047744k available (2210k kernel code, 17032k reserved, 919k data, 232k init, 130240k highmem)
Checking if this processor honours the WP bit even in supervisor mode... Ok.
Calibrating delay loop (skipped), value calculated using timer frequency.. 4405.99 BogoMIPS (lpj=2202999)
Security Framework v1.0.0 initialized
SELinux:  Initializing.
SELinux:  Starting in permissive mode
selinux_register_security:  Registering secondary module capability
Capability LSM initialized as secondary
Mount-cache hash table entries: 512
CPU: After generic identify, caps: 078bfbff e1d3fbff 00000000 00000000 00000000 00000000 00000000
CPU: After vendor identify, caps: 078bfbff e1d3fbff 00000000 00000000 00000000 00000000 00000000
CPU: L1 I Cache: 64K (64 bytes/line), D cache 64K (64 bytes/line)
CPU: L2 Cache: 512K (64 bytes/line)
CPU: After all inits, caps: 078bf3ff e1d3fbff 00000000 01000410 00000000 00000000 00000000
Intel machine check architecture supported.
Intel machine check reporting enabled on CPU#0.
Checking 'hlt' instruction... OK.
SMP alternatives: switching to UP code
Freeing SMP alternatives: 14k freed
ACPI: Core revision 20060707
CPU0: AMD Athlon(tm) 64 Processor 3200+ stepping 00
Total of 1 processors activated (4405.99 BogoMIPS).
ENABLING IO-APIC IRQs
..TIMER: vector=0x31 apic1=0 pin1=2 apic2=0 pin2=0
Using local APIC timer interrupts.
Brought up 1 CPUs
sizeof(vma)=84 bytes
sizeof(page)=32 bytes
sizeof(inode)=340 bytes
sizeof(dentry)=136 bytes
sizeof(ext3inode)=492 bytes
sizeof(buffer_head)=52 bytes
sizeof(skbuff)=176 bytes
checking if image is initramfs... it is
Freeing initrd memory: 3380k freed
NET: Registered protocol family 16
ACPI: bus type pci registered
PCI: PCI BIOS revision 2.10 entry at 0xf0031, last bus=1
PCI: Using configuration type 1
Setting up standard PCI resources
ACPI: Interpreter enabled
ACPI: Using IOAPIC for interrupt routing
ACPI: No dock devices found.
ACPI: PCI Root Bridge [PCI0] (0000:00)
PCI: enabled onboard AC97/MC97 devices
ACPI: PCI Interrupt Routing Table [\_SB_.PCI0._PRT]
ACPI: PCI Interrupt Link [LNKA] (IRQs 3 4 5 7 10 *11 14 15)
ACPI: PCI Interrupt Link [LNKB] (IRQs 3 4 5 7 *10 11 14 15)
ACPI: PCI Interrupt Link [LNKC] (IRQs 3 4 *5 7 10 11 14 15)
ACPI: PCI Interrupt Link [LNKD] (IRQs 3 4 5 *7 10 11 14 15)
ACPI: PCI Interrupt Link [LNKE] (IRQs 3 4 5 7 10 11 14 15) *0, disabled.
ACPI: PCI Interrupt Link [LNKF] (IRQs 3 4 5 7 10 11 14 15) *0, disabled.
ACPI: PCI Interrupt Link [LNKG] (IRQs 3 4 5 7 10 11 14 15) *0, disabled.
ACPI: PCI Interrupt Link [LNKH] (IRQs 3 4 5 7 10 11 14 15) *0, disabled.
Linux Plug and Play Support v0.97 (c) Adam Belay
pnp: PnP ACPI init
pnp: PnP ACPI: found 11 devices
usbcore: registered new driver usbfs
usbcore: registered new driver hub
PCI: Using ACPI for IRQ routing
PCI: If a device doesn't work, try "pci=routeirq".  If it helps, post a report
NetLabel: Initializing
NetLabel:  domain hash size = 128
NetLabel:  protocols = UNLABELED CIPSOv4
NetLabel:  unlabeled traffic allowed by default
pnp: 00:07: iomem range 0xfec00000-0xfec00fff has been reserved
pnp: 00:07: iomem range 0xfee00000-0xfee00fff has been reserved
pnp: 00:07: iomem range 0xfff80000-0xffffffff has been reserved
pnp: 00:0a: iomem range 0x0-0x9ffff could not be reserved
pnp: 00:0a: iomem range 0xc0000-0xdffff could not be reserved
pnp: 00:0a: iomem range 0xe0000-0xfffff could not be reserved
pnp: 00:0a: iomem range 0x100000-0x3ffeffff could not be reserved
PCI: Bridge: 0000:00:01.0
  IO window: 9000-0000
  MEM window: fc100000-00000000
  PREFETCH window 0x00000000d7f00000-0x00000000f7efffff
PCI: Setting latency timer of device 0000:00:01.0 to 64
NET: Registered protocol family 2
IP route cache hash table entries: 32768 (order: 5, 131072 bytes)
TCP established hash table entries: 131072 (order: 8, 1048576 bytes)
TCP bind hash table entries: 65536 (order: 7, 524288 bytes)
TCP: Hash tables configured (established 131072 bind 65536)
TCP reno registered
apm: BIOS version 1.2 Flags 0x03 (Driver version 1.16ac)
apm: overridden by ACPI.
audit: initializing netlink socket (disabled)
type=2000 audit(1443786217.603:1): initialized
highmem bounce pool size: 64 pages
Total HugeTLB memory allocated, 0
VFS: Disk quotas dquot_6.5.1
Dquot-cache hash table entries: 1024 (order 0, 4096 bytes)
SELinux:  Registering netfilter hooks
Initializing Cryptographic API
alg: No test for crc32c (crc32c-generic)
ksign: Installing public key data
Loading keyring
- Added public key BE845A7D9DFB2562
- User ID: CentOS (Kernel Module GPG key)
io scheduler noop registered
io scheduler anticipatory registered
io scheduler deadline registered
io scheduler cfq registered (default)
Boot video device is 0000:01:00.0
pci_hotplug: PCI Hot Plug PCI Core version: 0.5
Real Time Clock Driver v1.12ac
Non-volatile memory driver v1.2
Linux agpgart interface v0.101 (c) Dave Jones
agpgart: Detected AGP bridge 0
agpgart: AGP aperture is 64M @ 0xf8000000
Serial: 8250/16550 driver $Revision: 1.90 $ 4 ports, IRQ sharing enabled
serial8250: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
serial8250: ttyS1 at I/O 0x2f8 (irq = 3) is a 16550A
00:08: ttyS1 at I/O 0x2f8 (irq = 3) is a 16550A
00:09: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
brd: module loaded
Uniform Multi-Platform E-IDE driver Revision: 7.00alpha2
ide: Assuming 33MHz system bus speed for PIO modes; override with idebus=xx
VP_IDE: IDE controller at PCI slot 0000:00:0f.1
ACPI: PCI Interrupt 0000:00:0f.1[A] -> GSI 20 (level, low) -> IRQ 169
PCI: VIA IRQ fixup for 0000:00:0f.1, from 255 to 9
VP_IDE: chipset revision 6
VP_IDE: not 100% native mode: will probe irqs later
VP_IDE: VIA vt8237 (rev 00) IDE UDMA133 controller on pci0000:00:0f.1
    ide0: BM-DMA at 0xfc00-0xfc07, BIOS settings: hda:pio, hdb:pio
    ide1: BM-DMA at 0xfc08-0xfc0f, BIOS settings: hdc:DMA, hdd:DMA
Probing IDE interface ide0...
Probing IDE interface ide1...
hdc: LITE-ON DVDRW SOHW-832S, ATAPI CD/DVD-ROM drive
hdd: LITE-ON DVD SOHD-16P9S, ATAPI CD/DVD-ROM drive
ide1 at 0x170-0x177,0x376 on irq 15
Probing IDE interface ide0...
ide-floppy driver 0.99.newide
usbcore: registered new driver hiddev
usbcore: registered new driver usbhid
drivers/usb/input/hid-core.c: v2.6:USB HID core driver
PNP: No PS/2 controller found. Probing ports directly.
serio: i8042 KBD port at 0x60,0x64 irq 1
serio: i8042 AUX port at 0x60,0x64 irq 12
mice: PS/2 mouse device common for all mice
md: md driver 0.90.3 MAX_MD_DEVS=256, MD_SB_DISKS=27
md: bitmap version 4.39
TCP bic registered
Initializing IPsec netlink socket
NET: Registered protocol family 1
NET: Registered protocol family 17
Using IPI No-Shortcut mode
ACPI: (supports S0 S1 S3 S4 S5)
Initalizing network drop monitor service
Freeing unused kernel memory: 232k freed
Write protecting the kernel read-only data: 417k
Time: tsc clocksource has been installed.
ACPI: PCI Interrupt 0000:00:10.4[C] -> GSI 21 (level, low) -> IRQ 177
PCI: VIA IRQ fixup for 0000:00:10.4, from 5 to 1
ehci_hcd 0000:00:10.4: EHCI Host Controller
ehci_hcd 0000:00:10.4: new USB bus registered, assigned bus number 1
ehci_hcd 0000:00:10.4: irq 177, io mem 0xfdf00000
ehci_hcd 0000:00:10.4: USB 2.0 started, EHCI 1.00, driver 10 Dec 2004
usb usb1: configuration #1 chosen from 1 choice
hub 1-0:1.0: USB hub found
hub 1-0:1.0: 8 ports detected
ohci_hcd: 2005 April 22 USB 1.1 'Open' Host Controller (OHCI) Driver (PCI)
USB Universal Host Controller Interface driver v3.0
ACPI: PCI Interrupt 0000:00:10.0[A] -> GSI 21 (level, low) -> IRQ 177
PCI: VIA IRQ fixup for 0000:00:10.0, from 11 to 1
uhci_hcd 0000:00:10.0: UHCI Host Controller
uhci_hcd 0000:00:10.0: new USB bus registered, assigned bus number 2
uhci_hcd 0000:00:10.0: irq 177, io base 0x0000b400
usb usb2: configuration #1 chosen from 1 choice
hub 2-0:1.0: USB hub found
hub 2-0:1.0: 2 ports detected
ACPI: PCI Interrupt 0000:00:10.1[A] -> GSI 21 (level, low) -> IRQ 177
PCI: VIA IRQ fixup for 0000:00:10.1, from 11 to 1
uhci_hcd 0000:00:10.1: UHCI Host Controller
uhci_hcd 0000:00:10.1: new USB bus registered, assigned bus number 3
uhci_hcd 0000:00:10.1: irq 177, io base 0x0000b800
usb usb3: configuration #1 chosen from 1 choice
hub 3-0:1.0: USB hub found
hub 3-0:1.0: 2 ports detected
usb 1-4: new high speed USB device using ehci_hcd and address 2
ACPI: PCI Interrupt 0000:00:10.2[B] -> GSI 21 (level, low) -> IRQ 177
PCI: VIA IRQ fixup for 0000:00:10.2, from 10 to 1
uhci_hcd 0000:00:10.2: UHCI Host Controller
uhci_hcd 0000:00:10.2: new USB bus registered, assigned bus number 4
uhci_hcd 0000:00:10.2: irq 177, io base 0x0000c000
usb usb4: configuration #1 chosen from 1 choice
hub 4-0:1.0: USB hub found
hub 4-0:1.0: 2 ports detected
ACPI: PCI Interrupt 0000:00:10.3[B] -> GSI 21 (level, low) -> IRQ 177
PCI: VIA IRQ fixup for 0000:00:10.3, from 10 to 1
uhci_hcd 0000:00:10.3: UHCI Host Controller
uhci_hcd 0000:00:10.3: new USB bus registered, assigned bus number 5
uhci_hcd 0000:00:10.3: irq 177, io base 0x0000c400
usb usb5: configuration #1 chosen from 1 choice
hub 5-0:1.0: USB hub found
hub 5-0:1.0: 2 ports detected
usb 1-4: configuration #1 chosen from 1 choice
hub 1-4:1.0: USB hub found
hub 1-4:1.0: 3 ports detected
SCSI subsystem initialized
libata version 3.00 loaded.
sata_promise 0000:00:08.0: version 2.12
ACPI: PCI Interrupt 0000:00:08.0[A] -> GSI 18 (level, low) -> IRQ 185
scsi0 : sata_promise
scsi1 : sata_promise
scsi2 : sata_promise
ata1: SATA max UDMA/133 mmio m4096@0xfd600000 ata 0xfd600200 irq 185
ata2: SATA max UDMA/133 mmio m4096@0xfd600000 ata 0xfd600280 irq 185
ata3: PATA max UDMA/133 mmio m4096@0xfd600000 ata 0xfd600300 irq 185
usb 1-7: new high speed USB device using ehci_hcd and address 3
usb 1-7: configuration #1 chosen from 1 choice
ata1: SATA link up 1.5 Gbps (SStatus 113 SControl 300)
ata1.00: ATA-6: WDC WD2000JD-00HBB0, 08.02D08, max UDMA/133
ata1.00: 390721968 sectors, multi 0: LBA48 
ata1.00: configured for UDMA/133
ata2: SATA link up 1.5 Gbps (SStatus 113 SControl 300)
ata2.00: ATA-6: WDC WD2000JD-00HBB0, 08.02D08, max UDMA/133
ata2.00: 390721968 sectors, multi 0: LBA48 
ata2.00: configured for UDMA/133
usb 1-4.1: new low speed USB device using ehci_hcd and address 4
  Vendor: ATA       Model: WDC WD2000JD-00H  Rev: 08.0
  Type:   Direct-Access                      ANSI SCSI revision: 05
SCSI device sda: 390721968 512-byte hdwr sectors (200050 MB)
sda: Write Protect is off
sda: Mode Sense: 00 3a 00 00
SCSI device sda: drive cache: write back
SCSI device sda: 390721968 512-byte hdwr sectors (200050 MB)
sda: Write Protect is off
sda: Mode Sense: 00 3a 00 00
SCSI device sda: drive cache: write back
 sda: sda1 sda2
sd 0:0:0:0: Attached scsi disk sda
  Vendor: ATA       Model: WDC WD2000JD-00H  Rev: 08.0
  Type:   Direct-Access                      ANSI SCSI revision: 05
SCSI device sdb: 390721968 512-byte hdwr sectors (200050 MB)
sdb: Write Protect is off
sdb: Mode Sense: 00 3a 00 00
SCSI device sdb: drive cache: write back
SCSI device sdb: 390721968 512-byte hdwr sectors (200050 MB)
sdb: Write Protect is off
sdb: Mode Sense: 00 3a 00 00
SCSI device sdb: drive cache: write back
 sdb: sdb1 sdb2
sd 1:0:0:0: Attached scsi disk sdb
sata_via 0000:00:0f.0: version 2.3
ACPI: PCI Interrupt 0000:00:0f.0[B] -> GSI 20 (level, low) -> IRQ 169
sata_via 0000:00:0f.0: routed to hard irq line 10
scsi3 : sata_via
scsi4 : sata_via
ata4: SATA max UDMA/133 cmd 0xe400 ctl 0xe000 bmdma 0xd000 irq 169
ata5: SATA max UDMA/133 cmd 0xd800 ctl 0xd400 bmdma 0xd008 irq 169
usb 1-4.1: configuration #1 chosen from 1 choice
input: No brand KVM as /class/input/input0
input,hidraw0: USB HID v1.10 Keyboard [No brand KVM] on usb-0000:00:10.4-4.1
input: No brand KVM as /class/input/input1
input,hidraw0: USB HID v1.10 Mouse [No brand KVM] on usb-0000:00:10.4-4.1
ata4: SATA link down 1.5 Gbps (SStatus 0 SControl 300)
ata5: SATA link down 1.5 Gbps (SStatus 0 SControl 300)
Initializing USB Mass Storage driver...
scsi5 : SCSI emulation for USB Mass Storage devices
usb-storage: device found at 3
usb-storage: waiting for device to settle before scanning
usbcore: registered new driver usb-storage
USB Mass Storage support registered.
  Vendor: Generic   Model: USB SD Reader     Rev: 1.00
  Type:   Direct-Access                      ANSI SCSI revision: 00
sd 5:0:0:0: Attached scsi removable disk sdc
  Vendor: Generic   Model: USB CF Reader     Rev: 1.01
  Type:   Direct-Access                      ANSI SCSI revision: 00
sd 5:0:0:1: Attached scsi removable disk sdd
  Vendor: Generic   Model: USB SM Reader     Rev: 1.02
  Type:   Direct-Access                      ANSI SCSI revision: 00
sd 5:0:0:2: Attached scsi removable disk sde
  Vendor: Generic   Model: USB MS Reader     Rev: 1.03
  Type:   Direct-Access                      ANSI SCSI revision: 00
sd 5:0:0:3: Attached scsi removable disk sdf
usb-storage: device scan complete
device-mapper: uevent: version 1.0.3
device-mapper: ioctl: 4.11.6-ioctl (2011-02-18) initialised: dm-devel@redhat.com
device-mapper: dm-raid45: initialized v0.2594l
EXT3-fs: INFO: recovery required on readonly filesystem.
EXT3-fs: write access will be enabled during recovery.
kjournald starting.  Commit interval 5 seconds
EXT3-fs: dm-0: orphan cleanup on readonly fs
ext3_orphan_cleanup: deleting unreferenced inode 7766114
ext3_orphan_cleanup: deleting unreferenced inode 7766055
ext3_orphan_cleanup: deleting unreferenced inode 7766022
ext3_orphan_cleanup: deleting unreferenced inode 7766021
ext3_orphan_cleanup: deleting unreferenced inode 7766020
ext3_orphan_cleanup: deleting unreferenced inode 7766019
EXT3-fs: dm-0: 6 orphan inodes deleted
EXT3-fs: recovery complete.
EXT3-fs: mounted filesystem with ordered data mode.
SELinux:  Disabled at runtime.
SELinux:  Unregistering netfilter hooks
type=1404 audit(1443786254.111:2): selinux=0 auid=4294967295 ses=4294967295
ACPI: PCI Interrupt 0000:00:0a.0[A] -> GSI 17 (level, low) -> IRQ 193
skge 1.6 addr 0xfde00000 irq 193 chip Yukon-Lite rev 7
skge eth0: addr 00:11:2f:08:28:5b
EDAC MC: Ver: 2.0.1 Nov 13 2012
hdc: ATAPI 40X DVD-ROM DVD-R CD-R/RW drive, 2048kB Cache, UDMA(33)
Uniform CD-ROM driver Revision: 3.20
EDAC MC0: Giving out device to k8_edac Athlon64/Opteron: DEV 0000:00:18.2
hdd: ATAPI 48X DVD-ROM drive, 254kB Cache, UDMA(33)
input: PC Speaker as /class/input/input2
PCI: Enabling device 0000:00:11.5 (0000 -> 0001)
ACPI: PCI Interrupt 0000:00:11.5[C] -> GSI 22 (level, low) -> IRQ 201
PCI: Setting latency timer of device 0000:00:11.5 to 64
gameport: EMU10K1 is pci0000:00:09.1/gameport0, io 0xa800, speed 1217kHz
sd 0:0:0:0: Attached scsi generic sg0 type 0
sd 1:0:0:0: Attached scsi generic sg1 type 0
sd 5:0:0:0: Attached scsi generic sg2 type 0
sd 5:0:0:1: Attached scsi generic sg3 type 0
sd 5:0:0:2: Attached scsi generic sg4 type 0
sd 5:0:0:3: Attached scsi generic sg5 type 0
Floppy drive(s): fd0 is 1.44M
codec_read: codec 0 is not valid [0xfe0000]
codec_read: codec 0 is not valid [0xfe0000]
codec_read: codec 0 is not valid [0xfe0000]
codec_read: codec 0 is not valid [0xfe0000]
FDC 0 is a post-1991 82077
PCI: Enabling device 0000:00:11.6 (0000 -> 0001)
ACPI: PCI Interrupt 0000:00:11.6[C] -> GSI 22 (level, low) -> IRQ 201
PCI: Setting latency timer of device 0000:00:11.6 to 64
ACPI: PCI interrupt for device 0000:00:11.6 disabled
VIA 82xx Modem: probe of 0000:00:11.6 failed with error -13
ACPI: PCI Interrupt 0000:00:09.0[A] -> GSI 16 (level, low) -> IRQ 209
Installing spdif_bug patch: Audigy 2 [SB0240]
lp: driver loaded but no devices found
NET: Registered protocol family 10
lo: Disabled Privacy Extensions
IPv6 over IPv4 tunneling driver
sit0: Disabled Privacy Extensions
[drm] Initialized drm 1.0.1 20051102
ACPI: PCI Interrupt 0000:01:00.0[A] -> GSI 16 (level, low) -> IRQ 209
[drm] Initialized radeon 1.25.0 20060524 on minor 0
ACPI: Power Button (FF) [PWRF]
ACPI: Power Button (CM) [PWRB]
ACPI: Sleep Button (CM) [SLPB]
ACPI: Mapper loaded
dell-wmi: No known WMI GUID found
md: Autodetecting RAID arrays.
md: autorun ...
md: ... autorun DONE.
device-mapper: multipath: version 1.0.6 loaded
device-mapper: table: 253:2: mirror: Device lookup failure
device-mapper: ioctl: error adding target to table
device-mapper: ioctl: device doesn't appear to be in the dev hash table.
hdc: command error: status=0x51 { DriveReady SeekComplete Error }
hdc: command error: error=0x54 { AbortedCommand LastFailedSense=0x05 }
ide: failed opcode was: unknown
ATAPI device hdc:
  Error: Illegal request -- (Sense key=0x05)
  Illegal mode for this track or incompatible medium -- (asc=0x64, ascq=0x00)
  The failed "Read 10" packet command was: 
  "28 00 00 00 00 00 00 00 02 00 00 00 00 00 00 00 "
end_request: I/O error, dev hdc, sector 0
EXT3 FS on dm-0, internal journal
kjournald starting.  Commit interval 5 seconds
EXT3 FS on sdb1, internal journal
EXT3-fs: mounted filesystem with ordered data mode.
Adding 2031608k swap on /dev/VolGroup00/LogVol01.  Priority:-1 extents:1 across:2031608k
powernow-k8: Pre-initialization of ACPI failed
powernow-k8: Found 1 AMD Athlon(tm) 64 Processor 3200+ processors (1 cpu cores) (version 2.20.00)
powernow-k8: BIOS error - no PSB or ACPI _PSS objects
Loading iSCSI transport class v2.0-871.
802.1Q VLAN Support v1.8 Ben Greear <greearb@candelatech.com>
All bugs added by David S. Miller <davem@redhat.com>
libcxgbi:libcxgbi_init_module: tag itt 0x1fff, 13 bits, age 0xf, 4 bits.
libcxgbi:ddp_setup_host_page_size: system PAGE 4096, ddp idx 0.
Chelsio T3 iSCSI Driver cxgb3i v2.0.0 (Jun. 2010)
iscsi: registered transport (cxgb3i)
cnic: Broadcom NetXtreme II CNIC Driver cnic v2.5.7 (July 20, 2011)
Broadcom NetXtreme II iSCSI Driver bnx2i v2.7.0.3 (Aug 04, 2011)
iscsi: registered transport (bnx2i)
iscsi: registered transport (tcp)
iscsi: registered transport (iser)
iscsi: registered transport (be2iscsi)
ip6_tables: (C) 2000-2006 Netfilter Core Team
ip_tables: (C) 2000-2006 Netfilter Core Team
Netfilter messages via NETLINK v0.30.
ip_conntrack version 2.4 (8185 buckets, 65480 max) - 228 bytes per conntrack
skge eth0: enabling interface
ADDRCONF(NETDEV_UP): eth0: link is not ready
skge eth0: Link is up at 100 Mbps, full duplex, flow control tx and rx
ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
Bluetooth: Core ver 2.10
NET: Registered protocol family 31
Bluetooth: HCI device and connection manager initialized
Bluetooth: HCI socket layer initialized
Bluetooth: L2CAP ver 2.8
Bluetooth: L2CAP socket layer initialized
Bluetooth: RFCOMM socket layer initialized
Bluetooth: RFCOMM TTY layer initialized
Bluetooth: RFCOMM ver 1.8
Bluetooth: HIDP (Human Interface Emulation) ver 1.1
hdc: command error: status=0x51 { DriveReady SeekComplete Error }
hdc: command error: error=0x54 { AbortedCommand LastFailedSense=0x05 }
ide: failed opcode was: unknown
ATAPI device hdc:
  Error: Illegal request -- (Sense key=0x05)
  Illegal mode for this track or incompatible medium -- (asc=0x64, ascq=0x00)
  The failed "Read 10" packet command was: 
  "28 00 00 00 00 00 00 00 02 00 00 00 00 00 00 00 "
end_request: I/O error, dev hdc, sector 0
hdc: command error: status=0x51 { DriveReady SeekComplete Error }
hdc: command error: error=0x54 { AbortedCommand LastFailedSense=0x05 }
ide: failed opcode was: unknown
ATAPI device hdc:
  Error: Illegal request -- (Sense key=0x05)
  Illegal mode for this track or incompatible medium -- (asc=0x64, ascq=0x00)
  The failed "Read 10" packet command was: 
  "28 00 00 00 00 00 00 00 02 00 00 00 00 00 00 00 "
end_request: I/O error, dev hdc, sector 0
eth0: no IPv6 routers present
agpgart: Found an AGP 3.5 compliant device at 0000:00:00.0.
agpgart: Putting AGP V3 device at 0000:00:00.0 into 4x mode
agpgart: Putting AGP V3 device at 0000:01:00.0 into 4x mode
[drm] Setting GART location based on new memory map
[drm] Loading R300 Microcode
[drm] writeback test succeeded in 1 usecs

you're getting errors on:

hdc: LITE-ON DVDRW SOHW-832S, ATAPI CD/DVD-ROM drive

I'd be tempted to remove that, reboot and see what happens. You're not running this from a liveCD are you?

Either way..pull the power from that drive, reboot and see what happens. Also, perhaps have a look at smartctl to see if the hard drives have any SMART errors.