For computer parts, Wanchai computer center is ok, but not the most interesting. I'd give that label to the Golden Computer Center in Sham Shui Po (exit D3 of the MTRC of the same name).
The one in Mong Kok has gone down lately, less shops, more high-end stuff, but there are still some good PC component shops.
Also in HK, you can return something within 7 days if it doesn't work. Beyond that you need to contact the distributor.
These buildings don't have everything though. I'd say that China and Thailand have a lot more to offer in terms of variety.
In Bangkok, the Chinatown area is really interesting. You can buy almost everything if you can find the street or building where a particular item is sold. Last time I was there I stumbled upon a watch market; you could buy them wholesale, by weight (not really, but it almost seemed like it).
The one in Mong Kok has gone down lately, less shops, more high-end stuff, but there are still some good PC component shops. Also in HK, you can return something within 7 days if it doesn't work. Beyond that you need to contact the distributor.
These buildings don't have everything though. I'd say that China and Thailand have a lot more to offer in terms of variety.
In Bangkok, the Chinatown area is really interesting. You can buy almost everything if you can find the street or building where a particular item is sold. Last time I was there I stumbled upon a watch market; you could buy them wholesale, by weight (not really, but it almost seemed like it).