Having read that RHEL/CentOS 6.4 came with new VMware drivers I checked whether this problem might perchance be fixed. It isn't. In the meantime I got a report that Windows 8 (64 bit) showed a similar problem. So, updated problem matrix (ESXi build omitted as it has no influence): Processor E5620 E3-1230 E3-1270V2 Windows XP/2003/2008 ok ok ok Windows 8 ? ? Panic CentOS 5.8 ok ok ok 2.6.18-308.13.1.el5 CentOS 6.2 ok ok ok(*) 2.6.32-220.7.1.el6.x86_64 CentOS 6.3 ok ok Panic 2.6.32-279.2.1.el6.x86_64 CentOS 6.4 ok ok Panic 2.6.32-358.0.1.el6.x86_64 (*) keyboard shows panic blink but system works fine otherwise Reminder of the problem description: trying to boot a VM with CentOS 6.3 or later on a VMware ESXi 4 host with a Xeon E3-1270V2 processor fails immediately after GRUB, with the VM locking up, console message: Sep 11 17:21:31.498: vmx| PANIC: early exception 0d rip 10:ffffffff81038879 error 0 cr2 0 and ESXi log messages: Sep 11 17:21:19.628: vcpu-0| RDMSR: unknown MSR[0x1a0] (read as zero): rip=0xffffffff810388db count=1 Sep 11 17:21:19.628: vcpu-0| RDMSR: unknown MSR[0x1a0] (read as zero): rip=0xffffffff810388db count=2 Sep 11 17:21:19.629: vcpu-0| X86Fault_Warning: vmcore/vmm64/cpu/interp.c:427: cs:eip=0x10:0xffffffff81038879 fault=13 Sep 11 17:21:19.632: vcpu-0| Vix: [1125838 vmxCommands.c:9609]: VMAutomation_HandleCLIHLTEvent. Do nothing. Sep 11 17:21:19.632: vcpu-0| MsgHint: msg.monitorevent.halt (sent) Sep 11 17:21:19.632: vcpu-0| The CPU has been disabled by the guest operating system. Power off or reset the virtual machine. -- Tilman Schmidt Phoenix Software GmbH Bonn, Germany -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 261 bytes Desc: OpenPGP digital signature URL: <http://lists.centos.org/pipermail/centos/attachments/20130312/d0ce0928/attachment-0003.sig>