Moving VMware Server, high kernel times

[Captain Fizz]

Hello folks,

Not sure if this is a Windows prob or Linux prob TBH.
Note: Bit of a Lunix noob

We moved our server from Mandriva with VMware 1.0.4 to an Ubuntu Server with VMWare server 1.0.6.
Mandriva: 2.6.17-13mdv (x86_64)
Ubuntu: 8.04 - 2.6.24-19-server (x86_32)

Ever since then we've had VERY high Kernel times within Win2k3:

Everything else works fine, the server is running quicker due to 2 x as much RAM, just occasional spurts of 100% for a few minutes is obviously having an impact.

Anyone got ideas on what could be causing it?

Would it be worth attempting to upgrade to VMWare Server v2 this weekend? Or would that not make any difference?

Thanks

EDIT - Old Host was Intel Xeon, new host is AMD Opteron.

 

[Captain Fizz]

Guest OS is 32bit.
As said I'm not that great with Linux and ended up installing the 32bit version of Ubuntu server as it was easier to install VMWare Server that way.
(I know it's prob v easy to install, but I didn't find it that easy ^^ )

I've looked at the hardware compatibility list for ESXi, I take it I shouldn't worry if it's nowhere to be seen on there?
NEC2500 model range is nowhere in the PDF.
IE - Would ESXi even run on the box?

Thanks

EDIT - If not - you'd recommend a 64bit flavour of Linux too?
I can just scratch my head/google a bit more to get it installed OK.