This is a hard one to catch and very counter-intuitive. I have seen this a handful of times. I wrote this document last year but wanted to increase awareness of it in case anyone sees it in the field. If you are having PSOD's (even if they don't match exactly what is listed in this document) that are not explained by Hardware or VMware support then check if the server has a KVM attached. Even IBM supported KVM's can be related to this issue. It is a quick test to rule out simply disconnect the KVM device and reboot. If the problem goes away it was caused by that. General rule is only connect a KVM device to an ESX host if it is absolutely necessary and even then disconnect it as soon as possible.
VMware ESX fails to install, hangs during boot or PSOD's when using KVM device