I am trying to build a small virtualized testbed using some older Xeon-based servers that do not support Intel VT-x.

In their previous use, the servers were running VMware ESX 3.5. Is there a more up-to-date virtualization platform I could use?

Most solutions I have checked (KVM, VMware ESXi, and Microsoft Hyper-V) seem to require Intel VT extensions on the CPU. Is there any virtualization platform that still supports older hardware?


Virtualbox? Most today take advantage of the extensions in order to give decent performance and features, as you've discovered.

The ultimate solution may be to spend $400 on a whitebox system to run an up to date hypervisor.

  • As I didn't wan to spend much time on the setup (the old severs won't be around for much longer) Virtualbox proved to be the best option. When combined with phpvirtualbox (code.google.com/p/phpvirtualbox) it makes an excellent free solution for running VMs on older boxes. – m000 May 26 '12 at 13:01

ESXi 3.5 still works. The first servers that incorporated the Intel VT extensions appeared in late 2005/ early 2006... Given the five major jumps in Intel CPU technology since then, your best bet is to try to find a modern low-cost system for your testing.

If you don't find something new, any used servers manufactured in the past 5-6 years would be compatible.


You can run OpenVZ containers without VT-x. Proxmox does OpenVZ containers and their new release is based of Debian 6.

I'm running this on some old hardware and it works like a charm.


VMWare ESXi 4.x runs fine on Intel 64 bits CPUs without VT-x support. ESXi 5.x also but you need 2 CPUs or a little hack to get it to install after that it works like a charm. The only catch is you can't run mixed 32 bits/64 bits VMs loads or another bare metal hypervisor nested in a VM.

I have an old HP ML350 G4p server with a 3.0 GHz Xeon and 5 GB of RAM running ESXi 4.1 free with 4 VMs for all our servers/services DC, DNS, DHCP, TFTP, Mail, Web, FTP, Proxy/Fw etc. OS is Windows Server 2003 SP2 at the moment but I'm considering migrating to ESXi 5.x soon and Windows Server 2008 later.

So I would recommend you try ESXi 5.x free and if you need help you can contact me.

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