Successfully upgraded my Standalone ESXi Server from ESXi 5.0 to ESXi 5.1
I had standalone ESXi Server on PowerEdge T310 Server with ESXi 5.0 installed on Hard Disk.
I downloaded Dell Customized version ESXi 5.1 from this link.
www.dell.com/.../poweredge-r620
The download link page said :
"This ISO image should be used only to recover/reinstall the ESXi image to SD Card/USB Key on Dell Platforms."
Also my server (T310) was missing from the long list of servers under compatiblity section.
But another pdf document here
http://support.dell.com/support/edocs/software/eslvmwre/VS_5/Docs/ESXiDG/ESXi5DG.pdf
had listed my T310 from loaded from Harddrive to be compatible with ESXi 5.1.
I updated my BIOS to the latest version.(This is important, earlier when I had tried to install without this I had error while upgrading).
I upgraded my ESXi from CD created using downloaded Dell Customized ISO.
Its woking fine.
Vinay