Geforce GTX 295 - Review of Nvidia's final dual graphics card
Three weeks ago we published a preview of Nvidia's Geforce GTX 295 and now it's time for a full review of the card. What is the Geforce GTX 295 capable of in matters of power consumption, loudness and micro stuttering?
[Source: view picture gallery]
Today Nvida's new dual GPU card based on two 55 nanometer GT200b GPUs is finally launched. It is the first of Nvidia's gaming cards that exceeds the TFLOPS limit. This is achieved by two GPUs each of which has 240 Shader ALUs, 80 texture units and 28 ROPs with a 448 bit memory interface each. The Geforce GTX 295 is supposed to win back the performance crown for Nvidia since currently AMD has the fastest card with the dual GPU model Radeon HD 4870 X2.
Furthermore the GTX 295 is the first 55 nanometer product introduced to Nvidia's enthusiast section. The two GT200b chips are produced in the finer structure and thus can be run with on lower power consumption. Nvidia specifies the TDP of the card with 289 watt. This actually is three watt higher than the HD 4870 X2 is said to need, but a lot less than two GTX 260s with 182 watt each. And compared to the latter ones the GTX 295 has additional functional units. All important details are listed in the chart below.
GTX 295 reviewed at PC Games Hardware [Source: view picture gallery]
As it has been the case with the Geforce 9800 GX2, Nvidia uses a so called sandwich design for the GTX 295 (without the GX2 tag) Two PCBs with the two GPUs between them are cooled by a single cooling solution. Nvidia says this design has thermal benefits compared to AMD's tandem design. In contrast to the 9800 GX2 Nvidia uses bigger areas on the slot cover and the upper side of the card to exhaust the heated air from between the two PCBs of the GTX 295. The noise of the radial fan is rather unobtrusive and could be described as hissing; we couldn't hear drumming noises. If you are afraid of getting deaf because of the cooling, we can give an all clear even for our pre-production sample. From a subjective point of view we already had much louder cards in our Test Lab. At full workload the card is not - as expected - the appropriate choice for silent PCs, but in idle it is surprisingly quiet. See "Power Consumption, Loudness and Cooling” for more details.
Comparison: theoretical specifications
Nvidia Geforce
AMD Radeon
9800 GTX+
8800 Ultra
GTX 260-216
GTX 280
GTX 295*
HD 4870 X2*
HD 4870
Chip
G92
G80
GT200
GT200
2xGT200b
2xRV770
RV770
Architecture (Nanometer)
65/55nm
90
65
65
55
55
55
Transistors (Mio.)
754
681
1,400
1,400
???
2x965
965
Core frequency (MHz)
738
612
576
602
576
750
750
Shader ALU frequency (MHz)
1,836
1,512
1,242
1,296
1,242
750
750
Memory frequency (MHz)
1,100
1,080
999
1,107
999
1,800
1,800
Shader version
4.0
4.0
4.0
4.0
4.0
4.1
4.1
Shader ALUs
128
128
216
240
2x240
2x800
800
VRAM (MiByte)
512
768
896
1,024
2x896
2x1,024
512
Memory bus (Bit)
256
384
448
512
2x448
2x256
256
Memory type
GDDR3
GDDR3
GDDR3
GDDR3
GDDR3
GDDR5
GDDR5
MAD performance (GFLOP/s)
470
387,1
536,5
622,1
2x596,2
2x1,200
1,200
MAD+MUL/ADD performance (GFLOP/s)
705**
580.7**
804.8**
933.1**
2x894,2
2x1,200
1,200
Texture fillrate (MTex/s)
47,232
19,584
41,472
48,160
2x46,080
2x30,000
30,000
Memory bandwidth (MiByte/s)
70,400
103,680
111,888
141,696
2x111,888
2x115,200
115,200
Multi GPU
SLI, 3-W.-SLI
SLI
SLI
SLI, 3-W.-SLI
Q-SLI
Crossfire X
Crossfire X
PCI-E. power connector (6-Pin/8-Pin)
2x/0x
2x/0x
2x/0x
1x/1x
1x/1x
1x/1x
2x/0x
Two NVIO chips are working in the PCB sandwich of the GTX 295. According to Nvidia one is feeding the two Dual-Link DVI ports, while the other one is supplying data to the additional HDMI port. So up to three displays can be connected to the card.