Amal as in Amal Dudeha?
BTW tell the budget and preference m8, u want 512MB or 1GB version?
Powercolor HD4850 512MB is for 7K whilst 4870 from same manufacturer is for 9K. 4870 from other companies is above 10K that too for 512MB version.
1GB HD4870 from Powercolor is 11K. Powercolor is being suggested as they have good cooling solution for both HD4850 and HD4850 and these card are known for their hotness(pun intended).
HD4850 is also available in 1GB model with prices 7.7K(Powercolor) and upwards. My suggestion to you is to go for HD4770, its same as HD4850 with less power consumption and faster memory(GDDR5). Again Powercolor HD4770 512MB is available for 7.5K. Skipp Nvidia unless u want PissX .