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Click here… to search for XCY X35 I7-8550U 8/480GB Mini PC on Aliexpress
Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
Coupon (289.99 USD): BGFBXY
Coupon (390.59 USD): aff7off
Coupon (390.59 USD): bGpAnDacHeCk
(CouponsFromChina.com tip: just apply this code in your cart after clicking “Proceed to checkout”. Click to copy code and open shop)
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k
Old coupons (from the oldest to the newest): BGXCY004, BGXCY001, PICODICOM, BGXCYX3544, bgchinafest, BGBFCR29, BGCITYADS2019, BGBFXCY02, BGJPXCY35, BGXY3585, BGXY3586, BG20X35, BGX3886, BGX3888, BGXCY88
(these codes were not working in latest coupon update, but you can check them out anyway)
Price history and price alert
Here is price history (for all/most countries) for XCY X35 I7-8550U 8/480GB Mini PC.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).