Power requirements of 4770/4870

[dawgtuff]

Why does the 4870 require so much more power than the 4770? Aren't they of the same design?

 

[masteryoda34]

No, they arent the same design. In particular, the 4870 has a 55nm chip with 800 shaders, whereas the 4770 has a 40nm chip with 640 shaders. The 4770 also only has a 128bit memory interface versus the 256bit interface on the 4870.

 

[yh125d]

Very different cards.


If you gave us more info if you're considering upgrading though, we could help...

 

[FalseChristian]

The HD 4770 uses GDDR5 so its 128-bit bus is like a 256-bit GDDR3 bus.

 

[masteryoda34]

Originally posted by: FalseChristian
The HD 4770 uses GDDR5 so its 128-bit bus is like a 256-bit GDDR3 bus.

But the 4870 has GDDR5 AND a 256bit bus.