You can buy 8800GTX or 8800GTS they are at the rang of 4000-5000hkd, they are the newest and the fastest for games, It will support direct X 10, THis is the best and newest you can Buy with your quoted budget.
XFX's quality and price is very good and made in US.
If you are not using it for games
For video editing work station and need high quality video image. You can try Matrox Parhelia or QID series thier entry model start from 4000HKD to 30K HKD(
www.matrox.com) ( people use it with electronic microscope and medical equipment)
Also you can take a look at the Nvida Quattro series Quadro FX1500 is around 4000hkd and 3400 is 6000hkd and the 4500 from 12k-50k
For normal home use 8800GTX will be the best choice buy XFX or Winfast la
Also you can take a look
2006-11-21 11:40:48 補充:
for product on nvidia please look at
http://www.nvidia.com/page/home.html
2006-11-27 09:20:53 補充:
Regarding 8800GTX there was news about some minor manufacturing bugs in the first batch of product all have been 回收. New stock have come out already or soon