This 400 watt power supply is the replacement/upgrade you've been looking for in your Sony Vaio computers that use the weird shaped power suppy. The part numbers for those sony vaio power supplies are typically MJPC-300A2. This specially manufactured power supply is designed to be a perfect fit into your Sony Vaio.
Please note that some of the older Sony Vaio power supplies use a 3-wire fan control that comes from the motherboard. This power supply has its own internal fan control and does not need the input from the motherboard. As such, you may get an error when you boot your computer saying that the power supply fan is not working. You can ignore this message and possibly set up your bios to ignore this error.
Please note that upgrading to 500, 630, and 700 watts will increase the depth of the power supply from 4 inches to 6.5 inches. Make sure there is enough available depth in your system before upgrading in wattage.