7800GT SLI or single 7800 GTX 512 @1920x1200?

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Elfear

Diamond Member
May 30, 2004
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Originally posted by: michaelpatrick33
Has Nvidia made any mention of being able to SLI a 7800GTX 256 (I have a watercooled BFG at 521core and 1414mem) and a 7800GTX 512 (which I will, of course, watercool)? I already have a Seasonic 600 so I am not worried about power :)


Seems like one of the reviewers tried that and it didn't work. Can't remember which site it was off the top of my head.
 

videoclone

Golden Member
Jun 5, 2003
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My Overclocked X800GTO runs all my games at 1920x1200 without slowdown ... until i start slowing down i wont buy another card.

12 months down the track i'll probably grab a geforce 8600GT or whatever ^_^ for a very nice price and bring my FPS back to playable level's .. i think that?s the best way to approach buying videocards ... don?t go all out because there's always going to be something twice as fast down the track and the Midrange cards will be a little better then the previous high end.
 

Elfear

Diamond Member
May 30, 2004
7,163
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Here is a good article for you OP. It directly compares the 512Mb 7800GTX, the X1800XT, and SLI'd 7800GTs. Looks like the 7800GTs perform better.

Here is a quote from their conclusion:
"Two 7800 GTs generally fell in between the single and dual 7800 GTX 512 MB cards in terms of performance."
 

Hacp

Lifer
Jun 8, 2005
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Originally posted by: michaelpatrick33
Has Nvidia made any mention of being able to SLI a 7800GTX 256 (I have a watercooled BFG at 521core and 1414mem) and a 7800GTX 512 (which I will, of course, watercool)? I already have a Seasonic 600 so I am not worried about power :)


I doubt they will, as Even cards like the 6800GT and Ultra can't SLI.
 

jiffylube1024

Diamond Member
Feb 17, 2002
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Originally posted by: Hacp
Originally posted by: michaelpatrick33
Has Nvidia made any mention of being able to SLI a 7800GTX 256 (I have a watercooled BFG at 521core and 1414mem) and a 7800GTX 512 (which I will, of course, watercool)? I already have a Seasonic 600 so I am not worried about power :)


I doubt they will, as Even cards like the 6800GT and Ultra can't SLI with one another.

^ Fixed for clarity - the way you had it written had me scratching my head (sure 6800GT's and 6800Ultra's can be SLI'ed ;) ).
 

Capt Caveman

Lifer
Jan 30, 2005
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I've been contemplating the same decision as the OP and have a really dumb question. Can you overclock video cards that are running in SLI?

If yes, do you overclock each individually or are they considered one? And obviously if both cards don't oc the same, you need to keep them in sync which means lowest max oc of the two cards?

If no, my guess then the 7800GTX will be the better performer when overclocked?
 

Elfear

Diamond Member
May 30, 2004
7,163
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Originally posted by: Capt Caveman
I've been contemplating the same decision as the OP and have a really dumb question. Can you overclock video cards that are running in SLI?

If yes, do you overclock each individually or are they considered one? And obviously if both cards don't oc the same, you need to keep them in sync which means lowest max oc of the two cards?

If no, my guess then the 7800GTX will be the better performer when overclocked?

They do have to be oced together which means you take the lesser max of the two cards. With that being said, I still think the 7800GT's will outperform the 512MB 7800GTX. I'll post some results in the next week or two of a pair of oced 7800GT's and see how they compare with Nvidia's new beast.
 

nitromullet

Diamond Member
Jan 7, 2004
9,031
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Originally posted by: Madellga
Is SLI working on most games? New and Old?

A single card will be better always, no matter what.

The SLI setup must support/be supported in the game.

Is that done through the drivers? Or is it needed also game patching?

Regarding my hardware, I think it can handle both cases (except in situations like the summer 2003, we had 40C for some days...)

Yes, SLI will work in games old and new. NV provides profiles for most of the common games at the moment. If they don't provide a profile for a game you want to run, simply run the coolbits mod, which will give you the ability to create your own profile. Creating your own profile for SLI is about as easy as setting up any of the other settings in the NV control panel, so it's not hard to do. Games do not have to be programmed specially for SLI to work, but it does appear that games can be programmed by the developer to be "SLI aware" and to configure SLI on its own. FEAR is an example... No matter how you set it up, if you have two cards, FEAR will run it in the correct SLI mode. I have even tried disabling one of the cards, and it still runs in SLI mode. Short of physically removing the second card, there is no way of disabling SLI in FEAR. This is certainly the ideal situation, but it's not necessary and creating your own profiles isn't difficult at all.

Edit: That aside, I would go for the single 512MB GTX over the dual GT's. The performance/cost is roughly the same, but the GTX gives you the option to add another later or the simplicity of running a single card. IMO, SLI is only a viable option when you are pairing two of the top cards or you already have one card and are upgrading by adding the second card. There is no real compelling reason to get dual GT's over the single 512MB GTX.
 

RussianSensation

Elite Member
Sep 5, 2003
19,458
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Doom 3 - 2048x1536 4AA/8AF
7800GT SLI = 80.6
512mb = 61.8

HL2 Lost Coast - 2048x1536 HDR/16AF
7800GT SLI = 49.9
512mb = 46.4

Serious Sam II - 2048x1536 4AA/16AF
7800GT SLI = 55.7
51mb = 47.7

FEAR - 1280x960 4AA/16AF
7800GT SLI = 70.7
512mb = 51.6

BF2 - 1600x1200 4AA/16AF
7800GT SLI = Median Low = 76.0
512mb = 60

and 3dmark 05..oh wait that's not a game :)

Both are good options. But if you plan on overclocking I suppose 7800GTs will give you a greater advantage. You are technically overclocking 40 pipelines vs. 24 pipes. So an equivalent boost in mhz gets a higher return in theory. You could probably get 150mhz on the ram for 7800GTs or extra 300mhz on both but only 150mhz on 1 512. Also say taking 7800GTs to 470 from 400 nets 70x20 pipes x 2 cards = 2800 boost in fillrate vs. 625mhz over 550 on 512mb or 75x24 pipes = 1800.
 

VERTIGGO

Senior member
Apr 29, 2005
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Originally posted by: Elfear
Here is a good article for you OP. It directly compares the 512Mb 7800GTX, the X1800XT, and SLI'd 7800GTs. Looks like the 7800GTs perform better.

Here is a quote from their conclusion:
"Two 7800 GTs generally fell in between the single and dual 7800 GTX 512 MB cards in terms of performance."

What the? That pcper review is driving me crazy, did they run at 12x10 or 16x12? Garrr, those numbers are quite high for 16x12 i think...
 

jiffylube1024

Diamond Member
Feb 17, 2002
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I would go for the dual GT setup, simply because at around $300-$330 each, they're cheaper than a 512MB GTX can be had, and they place higher in benchmarks. A single card would be much better if performance was the same, but in this case it isn't.

Also, overclocking would probably tip it a bit further in favour of the GT's, since although the GTX can gain 100 MHz on the memory and 50MHz on the core, you can get about 200 MHz per GT on the memory, and a similar gain on the core.
 

shiznit

Senior member
Nov 16, 2004
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in in the same boat jiffy (thanks for buying my x2), 2x7800gt's are a little faster but 256mb ram in sli is still 256, and i really want 512 for COD2 (i'm in a COD1 clan, and i'm going to be playing cod2 a whole lot). looks like im gonna wait for the price to settle into the $550-600, sell the GT and then by a 512.
 

jiffylube1024

Diamond Member
Feb 17, 2002
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Originally posted by: shiznit
in in the same boat jiffy (thanks for buying my x2), 2x7800gt's are a little faster but 256mb ram in sli is still 256, and i really want 512 for COD2 (i'm in a COD1 clan, and i'm going to be playing cod2 a whole lot). looks like im gonna wait for the price to settle into the $550-600, sell the GT and then by a 512.

No problem about the X2 - looking forward to getting it! If COD2 does really benefit from 512MB (It didn't look like it according to the graphs, but I don't play it so it very well could stutter with only 256MB), than waiting for the 512MB GTX is probably the smart move. Hopefully availability improves over the next month, so it has the chance to drop in price. Low volumes keeps prices high...
 

Madellga

Senior member
Sep 9, 2004
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Thanks for all feedback. From all reviews I've read, 2 cards might be better due to the fact that they keep the minimum framerates higher.

Interesting also is that SLI GT is just a bit behind SLI GTX 256MB (less than 10%), but the price difference is much higher than that. And the GT SLI has a more potential overclock to offer than a GTX 256MB SLI.

Of course the new card in SLI beats everything away, but I think as consumers we must say Basta!

There was a time I could by a brand new card (Voodoo 2 $220, Voodoo 3 3000 $180) for a reasonable amount. A couple of generations later they raised to 300, 400, 500 and now 700.

Of course I would like to have the latest, but after cooling down my wish to buy for 2 days (the new GTX 512MB are sold out around here), I decided to stick with my GTX for the moment. My friend will keep the GT and the second GT (still sealed) goes back for a refund.

I will wait for next gen or perhaps for a nice price drop on the GTX 256MB to make a SLI system.