You won't be able to install ESXi 4.0 on an ML350 G4p. The minimum requirement is a G5, as Intel-VT must be available and supported by the chipset and CPU. I think this is due to the 64-bit nature of ESXi 4. Either way, the G4 is not on the HCL for ESXi 4.0 or 4.0U1:
http://www.vmware.com/resources/compatibility/search.php
Note: selected ESXi 4.0 Installable with keywords "ML530" leaving all others at "All"
I'm sorry but this is COMPLETELY INCORRECT! If the first poster would have done a search for ML350g4p on the forum you would have found many posts that I have started.
Bottom line. I own an HP ML350g4p and I am running ESXi4. Now this is an unsupported server in that it is not listed on VMware's HCL. However, this does not mean that it does not work only that VMware and HP will not help you if you run into trouble.
I have done extensive testing of the ML350g4p with both ESXi 3.5 Update 4 and ESXi 4 Update 1. Both work. NOTE that what ever version you go with even if you want to go for classic ESX 3 or 4, you will NOT be able to run 64bit virtual machines. Nothing you can do I've done much research and attempted to find a solution. This server can only run 64bit OSs in native mode (not virtual).
My recommendation as you are new to VMware and virtualisation is to go for ESXi 4 and not the classic version. VMware are very slowly going to move from the service console and ESX for the slimmer ESXi 4.
Anyway I hope this clears things up! If you need help regarding firmware updates and other HP related stuff and/ or VMware help with this specific server you can contact me. I can guide you since I have the exact same hardware and also started out without any VMware knowledge until many months ago.
Good luck
P.S. You don't want to install HP's customised version of ESXi if you are going for version 4. It does not provide any benefits as unfortunately the CIM providers (basically things that can speak to your hardware and get health information) do nothing for this particular server. If however you go with ESXi 3.5 U4 then I suggest you download the HP version as those CIMs do provide health info for this server. I have tried this in multiple combinations and this will save you time and sanity :smileywink:
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