It is true that there are many desktops and laptops support that USB ports left alive while shut down so that we can charge any gadget through it. I also have it with my Samsung Netbook and Gigabyte desktop. Btw, I've read your gateway DX4860 specification, it doesn't seem to support that capability. But if you want to make sure of it, you can try find out if there is power feature software/utility from the factory. If it isn't then probably it doesn't.