You need to watch the amp draw specs of the CGX, especially the draw when slewing. The CGX documentation says a minimum of 4amps, but you need to allow headroom (I suggest at least 6 amps). In the field, if your running off a 12v car battery, there is not usually any issues. But at home, or in your observatory, running off AC to DC conversion, it's a good idea to stick with a well known reliable product, like the Bintel power supply (which i have used for six years to drive my CGX.)
I use and recommend this one:
https://www.bintel.com.au/product/powertech-12vdc-7-5a/
As far as the ebay one mentioned below is concerned, I see no evidence that it contains a fan to cool it, the Bintel one does.