You need to be careful, trying to put 220v through a 110v circuit will damage the device and invalidate the warranty.
It does of course depend on the device as to whether it is compatible with the voltage in Singapore. You said you put the device in low power mode, this is not good as the power you are putting through it is 220v, what it needs is stepping down to 110v, so you need to buy a voltage regulator that will do that, surge protectors do not step down the voltage but keep it at a constant, in your case a still too high 220v.
Most laptop chargers are what is known as switch-able, this is usually auto sensing multi-voltage and does not require your intervention to change the voltage. Look for the power label if it states 110~240v then it is switch-able. In this case it should be OK to run with no voltage changes required.
There are also some PC's that have a voltage regulator built in but most of these require a manual switch from the 110 to 220v. Again running 220v when the 110v is enabled usually results in the power adapter going bang.
Universal adapters are often just multi socket ends in differing sizes and not multi voltage, you need to ensure that any adapter you get steps the voltage down to the US rated 110v if the power adapter that comes with the "item" is not capable of switching between the two voltages automatically or manually.
20+ Years Experience - Senior Technician - Electronbox Mijas, España
Intel Channel Partner and a Member of the Microsoft Partner Network.