Can my PC handle 2 GTX 480 in SLI
  2 / 2    
[quote name='patman' post='1033622' date='Apr 4 2010, 07:22 AM']Well if you see that 1 GTX480 takes > 400 W under load.
That means a SLI config will drain more than 800W.

Good luck running the rest (an OC) with less than 200W.[/quote]

Well, as I understand, in SLi the second card, even at full load, doesn't pull the same power as the first will and thus the power draw isn't literally doubled. I don't think the memory on the second card is used at all or anything. I could be wrong though ... I am drawing this from memory from things I saw amongst the many reivews out there now and whatnot. My memory is foggy on it though.
[quote name='patman' post='1033622' date='Apr 4 2010, 07:22 AM']Well if you see that 1 GTX480 takes > 400 W under load.

That means a SLI config will drain more than 800W.



Good luck running the rest (an OC) with less than 200W.



Well, as I understand, in SLi the second card, even at full load, doesn't pull the same power as the first will and thus the power draw isn't literally doubled. I don't think the memory on the second card is used at all or anything. I could be wrong though ... I am drawing this from memory from things I saw amongst the many reivews out there now and whatnot. My memory is foggy on it though.

#16
Posted 04/04/2010 03:19 PM   
[quote name='MistaP' post='1033687' date='Apr 4 2010, 11:19 AM']I don't think the memory on the second card is used at all or anything.[/quote]

The graphics memory for clustered slave GPUs is used in the same regards it would be under independent conditions; to store frame buffers, the color/depth buffer, the stencil buffer, serve as a texture cache, so on and so forth. The graphics cards all act exactly the same way in SLI as they would outside of it. What a lot of people don't understand is that the memory isn't [i]additive[/i] in SLI - it's not pooled between devices and used as general storage like some would expect - but it absolutely remains functional.
[quote name='MistaP' post='1033687' date='Apr 4 2010, 11:19 AM']I don't think the memory on the second card is used at all or anything.



The graphics memory for clustered slave GPUs is used in the same regards it would be under independent conditions; to store frame buffers, the color/depth buffer, the stencil buffer, serve as a texture cache, so on and so forth. The graphics cards all act exactly the same way in SLI as they would outside of it. What a lot of people don't understand is that the memory isn't additive in SLI - it's not pooled between devices and used as general storage like some would expect - but it absolutely remains functional.

NVIDIA | Content & Technology
Technical Marketing Analyst, Gaming Products and Technologies

#17
Posted 04/04/2010 03:36 PM   
[quote name='Exitios' post='1033695' date='Apr 4 2010, 10:36 AM']The graphics memory for clustered slave GPUs is used in the same regards it would be under independent conditions; to store frame buffers, the color/depth buffer, the stencil buffer, serve as a texture cache, so on and so forth. The graphics cards all act exactly the same way in SLI as they would outside of it. What a lot of people don't understand is that the memory isn't [i]additive[/i] in SLI - it's not pooled between devices and used as general storage like some would expect - but it absolutely remains functional.[/quote]

Ah, I see. I knew it wasn't additive but I thought it wasn't even used either. Thanks for clearing that up

So then, is the sli power draw literally double that of a single card?
[quote name='Exitios' post='1033695' date='Apr 4 2010, 10:36 AM']The graphics memory for clustered slave GPUs is used in the same regards it would be under independent conditions; to store frame buffers, the color/depth buffer, the stencil buffer, serve as a texture cache, so on and so forth. The graphics cards all act exactly the same way in SLI as they would outside of it. What a lot of people don't understand is that the memory isn't additive in SLI - it's not pooled between devices and used as general storage like some would expect - but it absolutely remains functional.



Ah, I see. I knew it wasn't additive but I thought it wasn't even used either. Thanks for clearing that up



So then, is the sli power draw literally double that of a single card?

#18
Posted 04/04/2010 03:37 PM   
[quote name='MistaP' post='1033698' date='Apr 4 2010, 11:37 AM']So then, is the sli power draw literally double that of a single card?[/quote]

It depends on how well the workload is balanced between the GPUs, but since you should always assume the worst-case scenario to be true when considering hardware upgrades, yes, this will effectively double the electrical requirements of the graphics subsystem when at full load.
[quote name='MistaP' post='1033698' date='Apr 4 2010, 11:37 AM']So then, is the sli power draw literally double that of a single card?



It depends on how well the workload is balanced between the GPUs, but since you should always assume the worst-case scenario to be true when considering hardware upgrades, yes, this will effectively double the electrical requirements of the graphics subsystem when at full load.

NVIDIA | Content & Technology
Technical Marketing Analyst, Gaming Products and Technologies

#19
Posted 04/04/2010 03:47 PM   
You guys are right. Watts measured per system as a whole.

"[i]For anyone running a 2-Way SLI GTX 480 setup, we would suggest no less than a 800 watt power supply of good quality and surely we suggest a 1000 watt if you are overclocking anything in your system[/i]"

[url="http://www.hardocp.com/article/2010/03/26/nvidia_fermi_gtx_470_480_sli_review/7"]http://www.hardocp.com/article/2010/03/26/...80_sli_review/7[/url]
You guys are right. Watts measured per system as a whole.



"For anyone running a 2-Way SLI GTX 480 setup, we would suggest no less than a 800 watt power supply of good quality and surely we suggest a 1000 watt if you are overclocking anything in your system"



http://www.hardocp.com/article/2010/03/26/...80_sli_review/7

#20
Posted 04/04/2010 04:21 PM   
[quote name='Spikey101' post='1033603' date='Apr 4 2010, 11:23 AM']I'd wait and upgrade the system all together. 2 280s dont really need to be upgraded yet.[/quote]

I understand what you're saying but if one GTX 480 matches 2 GTX 280 in speed, I guess that 2 GTX 480 in SLI will give me at least 70 or 80% boost in gaming performance. I can say that if I still played games in 2D I would be more than satisfied with just 2 GTX 280, but considering the framerate drop caused by 3D vision I think it's not a bad idea to upgrade my video cards, will do a big difference considering tesselation and new Dx11 effects that the 400 series will bring to my system. I also read that the 400 series helps a lot decreasing ghosting in 3D.
I only play in 3D, 2D is longer an option....

I'm pretty happy with my Qx9650 at 3.8ghz, 790i Ultra SLI mobo and 4 GB Corsair Dominator DDR3 1800mhz. I only intend to replace all those components next year and I will have to trade everything as the new corei7 requires triple channel ram and x58 mobo. Anyway I would probally gain 10 or 15% better performance with the corei7 system comparing to my system. GPU upgrade is much more important in gaming performance than CPU, mobo and ram if you have a good setup and I guess mine is still pretty fast.


[quote name='patman' post='1033722' date='Apr 4 2010, 04:21 PM']You guys are right. Watts measured per system as a whole.

"[i]For anyone running a 2-Way SLI GTX 480 setup, we would suggest no less than a 800 watt power supply of good quality and surely we suggest a 1000 watt if you are overclocking anything in your system[/i]"

[url="http://www.hardocp.com/article/2010/03/26/nvidia_fermi_gtx_470_480_sli_review/7"]http://www.hardocp.com/article/2010/03/26/...80_sli_review/7[/url][/quote]


Heheh, I knew my Thermaltake toughpower 1000W could handle 2 GTX 480 in SLI with my overclocked Qx and ram. Cheers....
[quote name='Spikey101' post='1033603' date='Apr 4 2010, 11:23 AM']I'd wait and upgrade the system all together. 2 280s dont really need to be upgraded yet.



I understand what you're saying but if one GTX 480 matches 2 GTX 280 in speed, I guess that 2 GTX 480 in SLI will give me at least 70 or 80% boost in gaming performance. I can say that if I still played games in 2D I would be more than satisfied with just 2 GTX 280, but considering the framerate drop caused by 3D vision I think it's not a bad idea to upgrade my video cards, will do a big difference considering tesselation and new Dx11 effects that the 400 series will bring to my system. I also read that the 400 series helps a lot decreasing ghosting in 3D.

I only play in 3D, 2D is longer an option....



I'm pretty happy with my Qx9650 at 3.8ghz, 790i Ultra SLI mobo and 4 GB Corsair Dominator DDR3 1800mhz. I only intend to replace all those components next year and I will have to trade everything as the new corei7 requires triple channel ram and x58 mobo. Anyway I would probally gain 10 or 15% better performance with the corei7 system comparing to my system. GPU upgrade is much more important in gaming performance than CPU, mobo and ram if you have a good setup and I guess mine is still pretty fast.





[quote name='patman' post='1033722' date='Apr 4 2010, 04:21 PM']You guys are right. Watts measured per system as a whole.



"For anyone running a 2-Way SLI GTX 480 setup, we would suggest no less than a 800 watt power supply of good quality and surely we suggest a 1000 watt if you are overclocking anything in your system"



http://www.hardocp.com/article/2010/03/26/...80_sli_review/7





Heheh, I knew my Thermaltake toughpower 1000W could handle 2 GTX 480 in SLI with my overclocked Qx and ram. Cheers....

Windows 7 Home Premium 64 Bits - Core i7 2600K @ 4.5ghz - Asus Maximus IV Extreme Z68 - Geforce EVGA GTX 690 - 8GB Corsair Vengeance DDR3 1600 9-9-9-24 (2T) - Thermaltake Armor+ - SSD Intel 510 Series Sata3 256GB - HD WD Caviar Black Sata3 64mb 2TB - HD WD Caviar Black 1TB Sata3 64mb - Bose Sound System - LG H20L GGW Blu Ray/DVD/CD RW - LG GH20 DVD RAM - PSU Thermaltake Toughpower 1000W - Samsung S27A950D 3D Vision Ready + 3D HDTV SAMSUNG PL63C7000 3DTVPLAY + ROLLERMOD CHECKERBOARD

#21
Posted 04/08/2010 02:29 PM   
I know this thread is old but coudl you post some benchmarks in some games with your 790i gtx480sli setup. I'd like to see them for crysis, far cry 2, and bad company 2. Im looking at geting my second card with my e8400 and am trying to determine if its worth the price to upgrade to the q9550 or 9650.
I know this thread is old but coudl you post some benchmarks in some games with your 790i gtx480sli setup. I'd like to see them for crysis, far cry 2, and bad company 2. Im looking at geting my second card with my e8400 and am trying to determine if its worth the price to upgrade to the q9550 or 9650.

#22
Posted 07/14/2010 04:51 PM   
  2 / 2    
Scroll To Top