I have heard about this about EVGA's International Warranty too. You probably may need to ship it to the region's office, looks like it's Taiwan for APAC.
https://asia.evga.com/warranty/2011/
"All products purchased ON or AFTER July 1st, 2011 include a 3 year limited warranty from the date of purchase with a valid invoice. For users without a valid invoice, or users that have not purchased from an authorized reseller, the warranty begins from the date the product was shipped from EVGA’s warehouse. Registration is recommended."
Seems like it is ok to buy from Amazon SG.