SLI help

so, for christmas i am asking for another video card so I can do SLI, but will i need anything else other than another video card and a power supply?

if you could tell me what, and where would be the best place to get it at...that would be lovely

http://www.newegg.com/

best place i have found and at top 5 of reseller ratings for years.

they have to be the same model of card

they have to be SLI capable.

before you buy call the maker of the card you are thinking of and tell them what card you have now , what you are thinking of buying, and get confirmation it will work.

You will need more then just a video or power supply for SLI to work. You need to have a motherboard that will support SLI or Crossfire depending on the brand of card you are looking at. As far as I can tell at current most SLI and Crossfire Cards use or require PCI-express ports on the mother board. You need to investigate if your motherboard supports SLI or Crossfire and determine if you need a new motherboard. Not all mother boards support SLI. I would recommend a 500w to 600w and above power supply.

Upgrading all of these components is going to be a pain in the ass, but it will be probably be worth it.

What card do you have now? Are you sure you don't just want to get a better card altogether?

Upgrading to SLI motherboard, upgrading PSU, then installing the video cards, then reinstalling your operating system... it is going to be a pain, so make sure its worth it.

sysprep.exe from MS FTW

i already have an SLI mobo, and i have an xfx 7600gs 512 mb video card

and i was thinkin about getting a ocz gamexstream psu

I run a decent computer business building and repairing computers as a side thing.

There is one worry when buying your GPUs seperately. The V-BIOS might be a different version, and that can adversely effect the performance of the SLi interconnect or completely ruin it.

You have to get the identical card to what you have right now. That means you need to get another 7600GS from XFX with the same model number. make sure they havent had a V-BIOS revision either, or you may be up a creek without a paddle.

On a side note.

Your PSU (Power supply unit) needs to be at least 500 watts. But wattage is actually the last of your worries. The 12v total rail needs to be @ least 30amps, no less. So if it is a dual 12v rail PSU (which it should be if not triple) they need to be 15a each. I would say go with an SLi Approved PSU just to be safe. 17-19a on each rail of the 12v is best, mine is this one:

http://www.newegg.com/Product/Produc...82E16817256006

As for the graphics cards....

I may be wrong, but the system I built for a client the other day used a 7600GS, and if I am not mistaken, the 7600GS CANNOT run in SLi. Look @ the top of the video card. Does it have a connection slot? You need that.

Ok, I looked. http://www.newegg.com/Product/Produc...82E16814150190
I presume that is your card. You CANNOT do SLi with that card.

So, here is what I recommend you do.

Buy 2 of these:

http://www.newegg.com/Product/Produc...82E16814150185

The connector at the top will be able to support the SLi bridge that came with your motherboard. Hope this helps.

i think he said 512 MB so that couldnt be his card.

as for 7600 GS not being SLI capable check this.

http://www.newegg.com/Product/ShowIm... d+%2D+Retail

heheh, i might just go the easy way out and get a 7950

Why a 7950 when the 8800's are out now? Depending on the PSU you currently have you may or may not want to replace it.

Performance on a 7950 will beat that of two 7600GT's, and possibly cost around the same, when you factor in the cost of selling the 7600GT.

well, i dont have 700 bucks to spend :P

and i have a 400 watt psu

A 400 watt PSU wont power SLi very well, because it is doubtful the rails have a high enough ampere rating. 16-19A is what you need to run SLi without issues. Without the ampere rating @ that level, you can "undersurge" the core. That means that the electrons wont have enough flowthrough into the gates, and the card will lag from lack of cycle paths. TRANS: That is a bad thing.

Up your PSU to @ least a 500Watt, a 600+ watt would be better. Make sure it has @ LEAST DUAL 12v + rails to take the strain from that type of pull. My recommendation is to have @ LEAST 30A on your 12+, aka 15A on each rail. If you get a triple, make sure its @ least 48 (16A each).


If you look under specifications on newegg, the ampere rating can be found per rail.

This is not completely accurate. You can run 2 cards in SLi mode that are different manufacturer and also have a different v-bios but they must both be the same type of GPU example: (2 7900gts - not 1 7900gt and 1 7800gt). It is recommended to use cards with the same core/memory speed. The cards will only run as fast as the slowest one.

If you are running SLi you MUST have a PSU no smaller than 600w.

My system has 2 8800gts with a 700w OCZ psu. 4 HD's and 1 CDrom

Rubbish! My Hiper TypeR 580W is perfectly happy running two cards wihtout a problem.

does that mean all those 500 watt NVIDIA SLI CERTIFIED power supplies are wrong?

garbage compounded

EDIT

i am running a pair of nicely overclocked EVGA 7900 GS without a quibble or hickup

For SLi you must (and I repeat you must) have the following:

1. A very good power supply. I suggest PC Power & Cooling Turbo-Cool 510 ASL. I own the 510-SLi version but, that does not have 8-pin mobo connector for new generation of mobos.
2. Two SLi ready Video cards. I loved my 6600GTs in SLi (Leadtek Version). Now I run 2x7900GTs from eVGA.

If you don't have a lot of money to fork out, first invest as much as you can on the power supply. I recommend PCP&C as they are arguably the best IMHO. Then, invest in GPUs. I will suggest you get the GPUs that are 2nd or 3rd best in the current marketplace. This means if 7900s are in vogue now, go for 7600s unless you know that the game will have problems running on those GPUs. eVGA has decent customer service and 90 day upgrade policy.

If you don't invest in Power Supply, you are simply making a HUGE mistake that will cost you money down the road.

- Vel

i recently invested in the 610 silencer from them and have had no regrets.

as for the Leadtek 6600GT i only had the one (AGP) but loved it and it is in my backup pc as i type still working fine.

i liked the EVGA lifetime warranty and price over the Leadtek 3 year .

If you're thinking about buying two new cards to run an SLI setup, I would suggest forgetting about SLI altogether unless you have a very large monitor and are planning to play at resolutions like 2048x1536 and above. The need to run ultra-high resolutions is the the only really good reason to choose SLI over a buying a nice, powerful single card. At typical resolutions SLI and Crossfire are horribly inefficient. You're much better off buying a better single-GPU card than you are running two lesser cards in SLI. The "bang-for-the-buck" factor is really very poor. Skip the dual-card setup and buy yourself a nice 8800GTS instead. You'll be much better off. I've been down the SLI road twice now and both times I've been quite disappointed with the performance for the price. Until something better than SLI and Crossfire comes along I'm finished with dual-GPU setups. IMHO they're a waste of money...you pay 200% of the price for 125% - 175% of the performance (typically....this varies depending on the game). There are even still quite a few games out there that scarcely benefit from adding the 2nd card at all.

I have to agree with that in part.

When I built my SLi system I had a 24 inch dell 1920x1200 resolution monitor and had 300 bucks for GPU. I chose to run 2x6600GTs instead of one 6800GT. I derived the benefit as a single 6600GT could not have run GW with full blown AA and other nifty "quality" settings.

But, as time progressed, I upgraded to 7900GTs as I got some cash to spend. Now, my SLi setup is not utilized as much it was during my 6600GT days.

This is the reason why I suggested to buy older cards to save money so that you rip the benefits of dual cards over single one. I use the simple formula:

1.25 x Newcard Cost = 2 x Oldcard Cost

Also, it is very important to realize that you must have a very high resolution monitor to utilize SLi. SLi will become an issue if your monitor can't handle high resolution. I will suggest SLi setup for new HD monitors capable of 1920x1200 resolution or more. If you are running on standard 1600 resolution, I will suggest using a single GPU system.

More is not always better.

- Vel