[review]3-way SLI, a new gaming experience
Page 1: The cost of 3-way SLI
Page 2: 3-way SLI bridge
Page 3: 3-Way SLI platform settings and important remarks
Page 4: Test bed
Page 5: 3DMark06
Page 6: DX10:Lost Planet & DX9:FEAR
Page 7: DX10:Company of Heroes OF & Crysis
Page 8: DX10:Bioshock & UT3 Demo
Page 9: DX10:PTBoats & World in conflict & DX9:HL2:EP2
Page 10: Comparison
Page 11: 3-way SLI platform power consumption
Page 12: Final thoughts
3-way SLI platform power consumption
NV claims in their 3-way SLI configuration technical file that the whole platform require a 1100W or higher PSU with 6 PCI-E power connector.
We using a ZM1200M PSU supplied by SliverStone. It is a active PFC PSU, have six +12V power module, each of the module has a highest flow @ 17A. The total output is 95A, 1140W. It is suitable for 3-way SLI platform.
We use Seasonic Power Angle to record the actual power usage of the whole platform. The test is done in two ways:
1. Idle in windows Vista for 15 minutes.
2.Use ATITool to stress VGA cards for 15minutes.
Though the highest watt in the chart is 625W, but we did not begin to stress the CPU yet! In the previous 3DMark06 test we notice the highest power consumption is above 700W. So you may use a 900W or 800W PSU to run a 3-way SLI, but it may not stable.
December 27th, 2007 at 9:59 pm
“Donβt forget the Quad CrossfireX coming this January. Will AMD do better this time?”
Hehe, from a technical perspective, the reason why Nvidia chose to do a 3way SLI(not 4way or more) is that they wanted to have direct SLI connection between every video card. Using 2 SLI connectors, Nvidia’s solution utilizes the low latency of one hop connection. Compared to ATI’s quad crossfire, the data has to jump 3 hops from the top ATI video card all the way to the bottom card, which makes the latency 3 times as high, which will cause image synchronization issues, degrading performance.
Plus, Vista without SP1 currently only support 3 frames of forward rendering in AFR mode, thus putting the limit of SLI to 3 way. Now, SP1 will allow more GPUs, but ATI’s solution is limited to the release schedule of Vista SP1. We will see, it is getting interesting.
December 28th, 2007 at 5:45 am
FEAR is DX10?
December 28th, 2007 at 10:17 am
FEAR is DX9 game
December 28th, 2007 at 11:00 am
@Doug Friedman,
ya, 3 hops is not good, but you forgot the PCIe-2.0. ATI’s Quad CFX is based on PCIe-2.0. while 3-way SLI isn’t.the CFX connector itself is not as important as SLI connector.
but i really concern about the Catalyst..you know that is not a good driver
December 28th, 2007 at 11:06 am
Maybe I missed something, but I thought that 680i tri-sli is not as effective due to the middle slot being 8x not 16x and thus bringing the other 2 slots down as well.
December 28th, 2007 at 12:42 pm
yes 16+8+16 PCIe
December 29th, 2007 at 1:06 am
Nice review. A few edits needed though.
1. Title :
“[review]3-way SLI, a new gaming expreience”
Should be - “experience”
2. Page 3 :
“Important: switch between 2-way SLI and 3-way SLI is sample,”
Should be - “Important: To switch from 3-way SLI to 2-way SLI is simple,”
December 29th, 2007 at 2:09 pm
Thank you LaGUNaMAN, i already fix the bugs..
December 29th, 2007 at 2:20 pm
You’re welcome jeff, rock on!