The power supply cannot be upgraded.  Only 270 Watts - unable to add any decent graphics card.  Can't use generic ATX supply as Dell uses a custom power supply.  Also, if you want to add a hard drive,  you need to buy a power Y adapter cable.Updating to 3 stars.  You can upgrade the power supply, using a third party cable, but the size may be an issue.  I needed to remove the cover latch and replace the latch with magnets (too lazy to drill holes.)