Run ESX 4.0 on Vmware workstation with less than 2 GB RAM

ESX:

1. Install vSphere(ESX) with at least 2 GB memory
2. Login to the Service Console and type the following:

   vi /etc/vmware/init/init.d/00.vmnix

3. Change the following line to the desired value:

   RequiredMemory=2064384

4. Shutdown the virtual machine and change the VMs memory and boot it up!

Thanks Mark for the comment on ESXi:

1. Install vSphere(ESXi) with at least 2 GB memory
2. Login to the console via the “unsupported” method.
3. Edit the file /etc/vmware/esx.conf and add the following line:

   /vmkernel/minMemoryCheck = “false”

4. Save the file and shutdown ESXi, change the memory and boot it up!

Source: -Yellow-Bricks