Username:
Password:
Remember Me?
   Lost your password?
Search



640 Shader, 40nm and GDDR5 for less than 100 Euros

Review: Ati RadeonHD 4770 vs. HD 4850 & Geforce 9800 GT

The Radeon HD 4770 is the first desktop graphics card with an RV740 GPU in 40 nanometer structure. Ati's new card competes with the Radeon HD 4850, Geforce 9800 GT and Co.


With the Radeon HD 4770, the first graphics card with "40 nanometer GPU” AMD wants to enter the crowded sector of sub 100 Euros graphics cards. We tested with up-to-date drivers and with common games like Call of Duty: World at War (dt.), Race Driver Grid or Fallout 3 if the card can succeed in its field of operation.

Radeon HD 4770 Launch-Review
 
Radeon HD 4770 Launch-Review [Source: view picture gallery]


Radeon HD 4770 Launch-Review (21)
 
Radeon HD 4770 Launch-Review (21) [Source: view picture gallery]
Due to the 40 nanometer technology and the slim 128 Bit memory interface the production costs and thus the prices for the customers are supposed to be kept low. The GDDR5 is expensive, but it runs much better than according GDDR3 chips. The number of operating units and the clock speeds indicate a performance level between HD 4830 and HD 4850 - all in all a quite interesting card that is introduced today. AMD expects a price between 90 and 100 Euros for the market introduction.

Ati Radeon HD 4770: Technical specifications
We want to keep it short and summarized the most important specifications in the table below. The RV740 chip is divided into 8 SIMD units with 16 optimized 5-way ALUs each. Each of the SIMDs has access to a Quad TMU so that all in all 32 texture values can be handled per clock.






Tech-Specs AMD Radeon Nvidia Geforce  
Graphics card HD 3870 HD 4670 HD 4770 HD 4830 HD 4850 9600 GT 9800 GT 9800 GTX
Chip RV670 RV730 RV740 RV770 RV770 G94 (b) G92(b) G92(b)
Structure (Nanometer) 55 55 40 55 55 65 / 55 65 / 55 65 / 55
Transistors (Mio.) 666 514 826 956 965 505 754 754
Chip frequency (MHz) 775 750 750 575 625 650 600 675
Shader ALUs frequency (MHz) 775 750 750 575 625 1,625 1,512 1,688
Memory frequency (MHz) 1,125 1,000 800 900 1,000 900 900 1,100
VRAM transactions per second (Mio) 2,500 2,000 3,600 1,800 2,000 1,800 1,800 2,200
Shader version 4.1 4.1 4.1 4.1 4.1 4.0 4.0 4.0
Shader ALUs 320 320 640 640 800 64 112 128
Double-Precision (FP64) Ja No Yes Yes Yes No No No
Raster operators (ROPs) 16 8 16 16 16 16 16 16
Texture units (INT/TMUs) 16/16 16/32 32/32 32/32 32/40 32/32 56/56 64/64
FP16 textures Single-Cycle Dual-Cycle Dual-Cycle Dual-Cycle Dual-Cycle Dual-Cycle Dual-Cycle Dual-Cycle
Default memory amount (MiB) 512 512 512 512 512 512 512 512
Memory bus/transmission (Bit) 256, DDR 128, DDR 128, QDR* 256, DDR 256, DDR 256, DDR 256, DDR 256, DDR
Memory type GDDR4 GDDR3 GDDR5 GDDR3 GDDR3 GDDR3 GDDR3 GDDR3
Calculation power (MADD, GFLOPS) 496 480 960 736 1000 208 338 432
Pixel fillrate (MTex/s) 12,400 6,000 12,000 9,200 10,000 10,400 9,600 10,800
Texture fillrate (filtered MTex/s) 12,400 24,000 24,000 18,400 25,000 20,800 33,600 43,200
Z fillrate (MZix/s) 24,800 12,000 24,000 18,400 20,000 83,200 76,900 86,400
Memory bandwidth (MByte/s) 72,000 32,000 51,200 57,600 64,000 57,600 57,600 70,400
PCI-E power connector (6-/8-Pin) 1x/0x 0x/0x 1x/0x 1x/0x 1x/0x 1x/0x 1x/0x 2x/0x
TDP/Max. Board-Power (Watt) 106 59 80 n.a. 110 95 110 156
Length PCB (mm, ca.) 229 168 208 229 229 228 228 267


The high data transfer rate of the GDDR5 - on our test sample there are 40 modules from Qimonda - compensates the slim, size efficient interface almost completely; thus the HD 4770 has enough bandwidth per Pixel/Texel (more is better of course). In contrast to the RV730 GPU on the HD 4670 the RV740 also supports the so called "Doubles”, FP64 or Double Precision, which are primarily used in extremely exact scientific calculations.

Picture gallery  (enlarge to view source)




--
Author: Spille, Vötter, Sauter (Apr 28, 2009)






Advertisement
Copyright © 2014 by Computec Media GmbH      About/Imprint  •  Terms/Conditions