SLi Question: Do I Need the Exact same card for SLI?

[Guest Dude-]

Hey. I have an Abit KN8-SLi motherboard and I am currently running an XFX 7800GT. I want to go SLi and take advantage of the motherboard. Do I need the literally exact same video card to do SLi? Or can I use another XFX card or any card for the matter. It is my understand that you need the physically exact same card to do SLi, but I wanted to check because everywhere I see my video card for sale, a newer more powerful one is available.

Edited May 30, 2006 by Dude-

[dwEEziL]

As best as I can remember, for nVidia's SLI implementation, you have to have IDENTICAL cards, down to the model number. Crossfire (ATI's dual card answer to nVidia's SLI) just needs Crossfire compatible cards and it will ramp down to match the less powerful of the two cards.

[Cujo]

you just need a second 7800gt. doesn't matter the brand, clock speeds, bios version. as long as it's a 7800gt core.

[Preacher]

the ATI has to be the same series like x1900xtx can use an x1900 series crossfire card but not an x1800 crossfire card.

 

For best performance nvidia as well as ATI suggests you use same make of card ie. if you have powercolor use another powercolor or bfg or whatever brand. This just reduces compatibility issues and mismatched pairs.

[Guest Dude-]

the ATI has to be the same series like x1900xtx can use an x1900 series crossfire card but not an x1800 crossfire card.

 

For best performance nvidia as well as ATI suggests you use same make of card ie. if you have powercolor use another powercolor or bfg or whatever brand. This just reduces compatibility issues and mismatched pairs.

 

 

Well what do you guys think I should do? Pay $300 for an XFX 7800GT which I paid like 4 months ago, or get a different 7800GT for $150. It has similar clock speeds but not the exact same.

[Laz.e.rus]

do what I always do...

 

Google it!!

[Kruten]

Where are you finding a 7800GT for that cheap? The lowest I'm seeing is like $290.

[Cujo]

kruten, are you sure you're looking at 7800gt and not 7900gt?

 

 

just go with the cheap one.

 

btw, what resolution do you run at and what is the max you can run at? why are you looking to add a second video card?

Edited May 30, 2006 by Cujo

[Kruten]

Well with a quick look at newegg.

 

 

http://www.newegg.com/Product/ProductList....&SubCategory=48

[Cujo]

that's funny cause i've heard the 7900gt can be had for that price. 7800gt right now is overpriced.

 

dude, any chance you can sell your 7800gt and just get a single 7900gtx?

 

also, answers to my earlier questions would go along way in getting a solid recommendation.

[Kruten]

that's funny cause i've heard the 7900gt can be had for that price. 7800gt right now is overpriced.

 

dude, any chance you can sell your 7800gt and just get a single 7900gtx?

 

also, answers to my earlier questions would go along way in getting a solid recommendation.

 

7900GTs don't cost much more.

[Guest Dude-]

You know selling my current 7800GT might not be a bad idea. Its sort of like the Geforce 2 Ultra. That card STILL costs a lot of money. Im also hearing that the 7800GT can outperform the 7900 or achieve the same performance in some cases...much like the Nvidia 4600 Ti which comes close to the 5800 Ultra.

 

I have found cards locally and online (7800GTs) for around $150-$200 but the cheapest Ive found the XFX is $275-$300. I really want to stay with XFX because they offer a lifetime replacement warranty incase anything goes wrong.

 

If someone else needs this UDF7 XFX card for the same reasons, it might be worth a lot of money as well, which would enable me to upgrade at the same time... The reason I want SLi is to increase my performance. I am doubling my RAM and going to SATA2 and at the same time I wanted to boost the video performance. Counter-Strike Source, my game of choice, already performs great but there is always room for improvement. I played a very similar setup computer recently with 2 7600GTs and I was impressed. Obviously Im not expecting twice the performance, but if I can find one for $200 its well worth it for me.

 

PS. I run 1280 Res with all the bells and whistlers except I dont run 16X A/F, just 8.

Edited June 1, 2006 by Dude-

[Tek-Almighty]

From what i've heard..you need same manufacturer and card...

 

hmm

 

I would sell your 7800 and buy a 7900 GT...good prices now and won't be able to ebay your 7800 for much longer.

[Cujo]

evga and bfg also offer lifetime warranties. at 1280 you will notice little to no improvement going to sli. you'll be able to turn up crazy levels of aa but that's about it. source is incredibly cpu limited. my 2.8ghz dual core amd is still cpu limited at 1600x1200 with everything full on a x1800xt pe.

 

tek, you don't need same manufacturer. just same gpu. ie. 7800gt needs a 7800gt not 7800gs or 7600gt. doesn't matter clock speeds, brand, bios version.

[dwEEziL]

Cujo, I've heard different. I've heard nVidia's implementation needs same model at least.

[Guest Dude-]

Cujo, I've heard different. I've heard nVidia's implementation needs same model at least.

 

 

ahh who is right!?!?

 

I believe that Source is very CPU limited, however I also take realworld experience first. Playing an almost identical computer with SLi 7600GTs made me believe that $200 would be a worthy investment. Of course, Im sure upgrading the CPU would be nice, a new CPU is out of the question for me. I feel extra RAM and SLi will make more of a difference. I wont do SLi if I have to pay $300 for a new card.

 

Unless everyone thinks upgrading to a dual core chip like a Manchestor or a Denmark is a much better investment. They are somewhat similar in cost. I mainly play Source.

 

So would SLi video card, extra 1 gig RAM, and SATA2 HD make more of a difference then something like an Operton 165 and 1 gig RAM?

[dwEEziL]

I'm sorry, I should have added at the end of my statement "but I'd imagine Cujo has been looking into it more recently than I."

 

I'll do a little researching and find out.

 

ADDED:

Based on the FAQ on the nVidia site, it looks like you have to have the same GPU/model but it no longer has to be from the same manufacturer.

8) Verify your two video cards match. For example, a GeForce 7800 GTX must be paired with another GeForce 7800 GTX. Likewise, a GeForce 6600 GT must be paired with another GeForce 6600 GT. However, using the latest Release 80 graphics drivers, NVIDIA GPUs sold by different manufacturers can be used together in SLI mode. For example, a GeForce 7800 GT from vendor ABC can be matched with a GeForce 7800 GT from vendor XYZ.

See answer number 8 at this link ===> http://tinyurl.com/opw4p

Edited June 1, 2006 by dwEEziL

[Cujo]

dude, i did do real world testing not that long ago. you will see very little difference in source in any of the upgrades you talk about. if the sli'ed 7600gts were faster then your 7800gt then there's something wrong with your system as they should only be marginally faster and your minimum fps (the most important number) should be identical. running at 1280 playing source you will not notice the extra ram as your aren't pushing your system enough.

 

you have yet to list your full system specs so i have no idea what any of the upgrades will give you.

 

also, switching from a sata1 to sata2 hard drive is a complete waste of money as the only difference is in buffer access. the hard drive still spins at a measly 7200rpm. think about getting a 74 or 150gig raptor instead. you will see more of an improvement.

 

here's my real world testing:

 

http://www.gamrs.co/forums/in...showtopic=22907

Edited June 1, 2006 by Cujo

[Guest Dude-]

""""""Can I mix and match graphics cards?

In order to provide optimal symmetric scaling, SLI Technology requires the NVIDIA GPU to match. For example, a GeForce 7800 GTX must be paired with another GeForce 7800 GTX. Likewise, a GeForce 6600 GT must be paired with another GeForce 6600 GT. However, using the latest Release 80 Graphics Drivers, NVIDIA GPUs sold by different manufacturers can be used together in SLI Mode. For example, a GeForce 7800 GT from vendor ABC can be matched with a GeForce 7800 GT from vendor XYZ. """""" ****I did not see that you found it before me above as well, thank you!*****

 

Straight from the guys themselves. So it seems you can infact use a different manufacturer, but the same GPU. I can find another 7800GT for $150. Cujo, what do you suggest I do. I thought I listed the computer specs but here we go.

 

AMD 64 3200+ (512kb L2 cache), 2x512 Mushkin DDR400 dual channel ram kit (nice mushkin), XFX 7800GT pci-e, Abit KN8-SLi motherboard, WD 80gig 7400rpm SATA drive, 8mb buff, onboard sound. Oh an Antec 650 watt (not 550) SLi powersupply. Raidmax case, steel with 4 case fans an PSU fan.

 

So if I have $300 to spend, what do I spend it on? I can either get another 7800GT and go SLi (I also play Episode 1, etc and might try some other games) and get another gig of performance RAM and save a little money. Or should I get a dual core AMD 939 chip? I feel like in heavy situations (complicated map, lots of people shooting, explosions, moving objects) I sometimes lag a little. What will help that the most?

Edited June 2, 2006 by Dude-

[Cujo]

i would upgrade to a dual core cpu and/or 2gigs of ram before getting sli. check this article below. yes, it's with a 7900gt heavily oced but notice it beats all 3 sli setups even up to 2048x1536 which leads me to believe that your card would at least not show any gain at 1280. if you were to go with a x2 3800 though you wouldn't see much difference in todays games cause they aren't multi threaded. you should look into overclocking your cpu. since you have mushkin you might be able to push your system pretty good. you saw the gains i got going from 2->2.5ghz. you should see even better numbers cause your vid card is quite a bit better then a x800xl.

 

http://www.theinquirer.net/?article=32139

 

(scroll down til you see the hl2 benchmarks. note: they test with 4x/8x so that's also significant.)

[akaM2]

cujo make me a computer and send it to me, mmmkay?

[Guest Dude-]

Well I guess I was trying to avoid overclocking. Id like this computer to last as long as possible. My CPU does run very cold though and I have read much about the AMD64's ability to overclock easily with stability. Im also very confident of the motherboard. But would I see gains? I guess I still for some reason feel the limitating factor is not CPU.

 

I was planning on getting a Raptor 74gig as well, regardless of whether there is improvement in games. Thats for just for sheer peace of mind.

 

I guess Ill start first and foremost with new RAM. DO I NEED THE SAME RAM? Do I need the same timing and stuff for maximum results? I was probably going to just buy the exact same RAM I already have, another dual channel 512x2 kit.

[Cujo]

for optimal performance sell your current 2x512mb sticks and buy 2x1gb sticks.

 

ocing your cpu will not lower the life of it significantly enough that you will ever notice. you should be able to get 2.4ghz easily. i'm can guarantee you that your biggets limiting factor on that system is your cpu. i've been building gaming computers for 8 years and i've read articles daily of different tests. did you not read my link a few above? how much clearer can i be? my vid card in that test wasn't even as good as yours and my cpu at 2.0ghz other than the dual core (which has extremely minimal impact in source) is identical to yours.

[Guest Dude-]

for optimal performance sell your current 2x512mb sticks and buy 2x1gb sticks.

 

ocing your cpu will not lower the life of it significantly enough that you will ever notice. you should be able to get 2.4ghz easily. i'm can guarantee you that your biggets limiting factor on that system is your cpu. i've been building gaming computers for 8 years and i've read articles daily of different tests. did you not read my link a few above? how much clearer can i be? my vid card in that test wasn't even as good as yours and my cpu at 2.0ghz other than the dual core (which has extremely minimal impact in source) is identical to yours.

 

 

I did read, and Ive read other things. Guess Im thickheaded. I will see if I can sell my RAM and get 2x1gig.

 

However, the last couple days for some reason my system has been slowing down in Source. It plays great, but afteyr 2 hours of play in 94 degree weather with humidity, it slows down to 25fps. Never happened before. My CPU isnt past 38 degrees C, but the system is about 40 C. However my GPU is about 60 C, but states the limit is far far above that. Whats going on there?

[Cujo]

it should get to full load temps long before 2 hours. also, your temps are just fine. i would look at your software.

 

 

i can tell you for sure that you don't have load temps of 38 and 40c with 94f ambient. maybe the outside is 94f? i know if it was 94f in my room my comp would be off and i'd be sitting on my couch in my boxers eating popsicles.

Edited June 5, 2006 by Cujo