i have a dell latitude c640 laptop with ddr sdram, P4, 1.20GHz,256 MB RAM, 30GB Hard disc and 512 KB L2 cache. I need to run windows7, ubuntu, Virtual Box/VMware, Xen, OpenvSwitch and may be creating 2 or more VMs at the same time. What upgrades do i need for cpu, motherboard, ram (at least 4GB required) or any other components so that, i may be able to REUSE this very laptop. Do let know the upgrade specifications, the component brands and approximate cost estimate. My mail id is: firstname.lastname@example.org
I'm afraid you need to upgrade that laptop into retirement there is no way on earth that you will be able to use that same chassis that laptop is from roughly 2002 even finding spare parts for that that might push the specification up , such as ram / new HDD will cost more than buying a new cheap laptop based on how difficult it will be source compatible ten year old parts.
The performance you will get out of a $300-$500 laptop compared to that current machine will be close to ten times what that is capable .