There is plenty of power to support the RX460 but I am unfamiliar with the Value Top brand. Since the PSU supplies all necessary power to everything, a good PSU can go a long way. Will it work? I'm sure.
It would be helpful to have more info on you're computers' spec's but as a rough guess... I would agree with iamthesaga.
As an example...
The GIGABYTE GV-RX460WF2OC-4GD has a power requirement of:
System PSU Limitation: 350W
GPU (TDP): 55W (Real)
Total Graphics Power (TGP): 85.00W (Real)
(Does not require a 6 pin connection, power is supplied from the motherboard)
As arcticwind said, having a parts list allows people to help you much easier.
But in a general sense, its not very good to go with cheap powersupplies, with a 460 a possible minimum wattage recommendation would be around 500w but a good quality PSU goes a long way. I would recommend something like these:
I would recommend going with higher wattage's just in case you want to upgrade or overclock in the future, a good middle ground would the 600B by EVGA
Just an FYI!
I saw that you also posted this question under "Support forums/Graphics".
Under Terms and conditions for the forums...
8. NO DUPLICATE OR REPEAT POSTS. If no one answers your question or responds to your post, please "bump" it rather than posting it again.