It's not worth while to buy your computer parts in China.
The profit margin on computer parts is very low.
Importer buys direct from the Mfgs in containers and makes 2-5% (10's millions of dollars at a time)
Wholesalers make 3-7% (hundred of thousands of dollars at a time)
Retailers make 5-10% (tens of thousand of dollars)
You can;t save money by buying from China, and there still the warranty issues. Retailers in China have to make a profit as well.
Besides, the more expensive parts are not made in China. Like Hard drive, Ram or CPU.
Even if you go direct to the Mfgs, they will not offer you the same price as they do to Importer. Count it all; from the Mfg to your hand, the profit made by everybody is 10-20%.
If you really want to save money, just shop around in Ottawa and you will find a good deal