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Off-Topic Discussion => General Discussion => Topic started by: Roanoke on December 14, 2005, 03:19:01 pm

Title: Dual GPUs
Post by: Roanoke on December 14, 2005, 03:19:01 pm
So what's the deal with Crossfire and Sli ? Can't say I care much for multiple screens so are there any other benefits ?
Gonna struggle to pay for one decent card )never mind two) but I am curious.
Title: Re: Dual GPUs
Post by: CP5670 on December 14, 2005, 03:29:44 pm
I'll post my thoughts on it in a few days once I get my machine running. Don't have a lot of time right now with the final exams and all.

You can't use more than one monitor in SLI though. (you can disable SLI in windows and then use four monitors, but only one works for games if SLI is being used)
Title: Re: Dual GPUs
Post by: Nuke on December 14, 2005, 03:53:50 pm
it should, in theory, double your fill rate. this is nothing new. i remember back in highschool when people would daisy chain their voodoo2s to the same effect, while i just went for a single, more advanced card (a 16 meg banshee card, overclocked by factory default, first video card that had a fan, it was sweet unless you tried to play glide games). really i think the same applies now, unless you are playing games alot, or have some special rendering requirements for graphic design, its pretty much useless. i would never spend more than $200 on a video card. if you go for a $300 or $400 video card, you will outrender every game on the shelf. if you go sli youre gonna need at least $500 in video cards and an expensive mobo to boot, and in all likelyhood a more expensive cooling meathod youl say bye bye to $1000 and you still need to buy a processor and some memory. when i built my computer i built it fast but i also kept it very simple, small case, single removable drive, single hard disk single processor and single video card. it all came to $900 and it can still make > 60 fps in quake 4. its still way better than what the consoles do. unless you absolutely need fill rate, which most people dont, or have alot of money to spend, which few people do, thenh its really just a useless waste of cash.
Title: Re: Dual GPUs
Post by: IceFire on December 14, 2005, 04:07:48 pm
So what's the deal with Crossfire and Sli ? Can't say I care much for multiple screens so are there any other benefits ?
Gonna struggle to pay for one decent card )never mind two) but I am curious.
Basically its a performance boost. Theres a bunch of things that two cards put together can sometimes do that a single card cannot.  A higher level of anti-aliasing for instance and rendering things a whole lot faster because the work is divided between the cards.

Both CrossFire and SLI have their advantages and disadvantages.  When it comes down to it for me....its too bloody expensive no matter what.  I'd rather spend good money on a single card solution and spend the rest elsewhere than on two cards...to give me "just that bit more" performance.  Really I think its overkill...you spend double the money and get maybe 30% performance boost.  Its significant but not worth it...unless you have money to burn.
Title: Re: Dual GPUs
Post by: CP5670 on December 14, 2005, 04:41:34 pm
SLI is a good idea if your monitor can take full advantage of it. Sure, it's expensive, but video cards are the one and only computer component that are actually worth spending a lot of money on. Unlike high end CPUs, memory, hard drives, cases and so on, you get tremendous performance increases over cheaper solutions.

The performance boosts from SLI over a single card are about 40-60% in slightly older (2004) games and over 90% in newer (2005) games with the 80 series drivers, provided that the resolution is sufficiently high. In older games there are still hefty improvements with the SLI AA modes.

I was originally going to buy a single, fast card instead, a 7800GTX 512MB, but that thing is $200 more than what I paid, almost impossible to find and significantly slower across the board. Two 7800GT COs are really the only video card setup that should be considered in the $500+ price bracket right now, unless you can afford two 512s.

If you want to go SLI though, you should get both cards at once. SLI is generally a poor choice as an upgrade option (getting one card now and another one later).

As for Crossfire, the X1800 master cards have just come out and are overpriced and in very low supply. That might be a more viable option in the future.
Title: Re: Dual GPUs
Post by: Roanoke on December 15, 2005, 11:33:41 am
Best case scenario monitor wise is gonna be a 19" TFT 1280x1024 native, which is frickin' incredible to what I'm running now.  A PC review I've got recorded Doom3 @ 46 fps running high detail and AAx4 with a 128MB 6800XT, Athlon64 3800+ and 512MB Ram so that's probably the sort of level I'm gonna be at, though even I can see plenty of room for improvement there.
Title: Re: Dual GPUs
Post by: Nuke on December 15, 2005, 05:17:36 pm
im happy with my 256 meg 6600. i never really have the cash to get the gt version of anything. i wanted more memory to support some of theese gargantuan textures im making as opposed to faster memory that was on other cards. it still does very well when dealing with alot of textures.
Title: Re: Dual GPUs
Post by: Grey Wolf on December 15, 2005, 10:37:33 pm
I'm really rather against the concept of SLI, both in implementation and the basic concept.
Title: Re: Dual GPUs
Post by: Kosh on December 16, 2005, 02:41:45 am
I'm really rather against the concept of SLI, both in implementation and the basic concept.


Why?


The basic concept is to see if they can sell twice as many video cards
Title: Re: Dual GPUs
Post by: Grey Wolf on December 16, 2005, 02:35:45 pm
I'm viewing it from the consumer's viewpoint. Paying twice the money for 30% performance gain (if you're lucky) is, IMHO, a waste of money.
Title: Re: Dual GPUs
Post by: CP5670 on December 16, 2005, 05:04:07 pm
I don't know where you're getting this 30% figure. Pretty much all modern games (except maybe HL2, which isn't very video card heavy) get at least 70% over a single card at 2048x1536, which usually increases to 90-100% when AA is turned on.  Anandtech, Firingsquad and Rage3D have several benchmarks showing this.

On a side note, I didn't get my motherboard today for some reason. :mad: Now I have to wait until monday to set this up. I guess I'll just do some FRED work in the meantime. The G15 keyboard I had ordered came in today though, so I can try that out.
Title: Re: Dual GPUs
Post by: Descenterace on December 16, 2005, 05:57:58 pm
Benchmarks mean nothing. Like statistics (which they are), they can prove anything.

You'll NEVER get 100% boost out of SLI or Crossfire because you have to take administrative overheads into account.
Title: Re: Dual GPUs
Post by: CP5670 on December 16, 2005, 06:42:32 pm
uh, what's your point? If you take a sufficiently large sampling of hardware review sites, you can get a pretty good picture of what the performance will be like. This is like arguing that the Intel GMA900 is faster than the 512MB GTX because the "benchmarks mean nothing." :p

You won't get exactly 100% but it gets very close in the newest games, like FEAR and COD2, or slightly older ones at high resolutions and AA.
Title: Re: Dual GPUs
Post by: Descenterace on December 16, 2005, 07:38:21 pm
OK, so modern benchmarking techniques are more useful...

Not so very long ago, it was fairly easy for graphics card manufacturers to cheat in benchmarks like 3DMark by coding the drivers to detect the benchmarking software and report false/misleading information.

I've still got an inherent distrust of benchmarks. I prefer to see a graphics card in operation before I trust the reviews. So far (from this generation) I've only seen the 7800GTX and the GT, but they're both so far ahead of my old X800XT it's hard to believe that the X1800s can be much better, considering that they're ATI's first venture into the world of Shader Model 3.
Title: Re: Dual GPUs
Post by: CP5670 on December 16, 2005, 11:56:09 pm
Oh, 3dmark is of course useless. I don't even bother looking at the 3dmark scores of cards anymore, especially since like all the older versions of the program, it has become CPU dependent now that the cards are hitting 10000. There are still a few IQ cheats going on, particularly on Nvidia's side with their default AF quality, but the 3dmark optimization wars during the FX/9x00 days are basically over.

I would have also liked to see this setup in person first, but I don't know many people in real life who are into games at all, much less ones who have SLI. I did quite a lot of research into this though and had a good idea of the noise, power consumption, image quality, and SLI limitations before I bought these cards.

The X1800XT actually looks pretty nice to me for the $500 or so that it's selling for now. The performance is overall right between a stock GTX 256MB and GTX 512MB and the high quality AF feature looks very nice. Although on the other hand, the HDR with AA thing is not really useful yet (no games currently support this feature and the HDR performance is not too great in the first place), there are a few games where it just inexplicably falls apart and you actually have to use the bloated CCC with all the X1x00 cards. I also admit to being slightly partial to Nvidia since their drivers work better with FS2 and I already know my way around all the 3rd party tweaking utilities well.

My original plan was to get the 512MB GTX, but no sane person would buy those at the $800+ prices they are going for at the moment, when they are even available that is. There was even a site selling for them $1100 recently and they sold out in two days, which is absurd given that one of these is slower than two GTs. The only thing I missed out on was the card's looks, as it has the coolest looking heatsink I have ever seen. :D

Two 7800GTs with GTX coolers and stock overclocks that make them about the same speed as reference GTXs for $600 was too good to pass up, especially considering that I also got Quake 4 and COD2 with the cards, which I was planning on getting anyway.
Title: Re: Dual GPUs
Post by: Descenterace on December 17, 2005, 04:29:43 am
My main reason for abandoning ATI is that their Linux drivers suck. Now I'm running a dual-boot system nVidia is pretty much my only choice.

Having seen the difference in speed between the 7800GTX and the X800XT in FEAR, I'm inclined to think I made the right decision :D

Yes, I know they can't really be compared since the X800XT is from the last generation.
Title: Re: Dual GPUs
Post by: CP5670 on December 17, 2005, 04:56:35 am
I'm coming from a 6800GT. It's been a great card for the last 18 months but it's limitations are showing now. I should get at least a triple speed increase at 2048x1536, where the last generation 6800/X800 cards do very badly due to an architectural weakness. I will probably either sell it on ebay (the AGP ones have held up their value pretty well and people tend to pay more for the BFG brand) or put in into a second computer.
Title: Re: Dual GPUs
Post by: Turnsky on December 17, 2005, 08:19:29 am
you'll want to see this beast of a thing then: http://www.digit-life.com/articles2/video/g70-8.html
Title: Re: Dual GPUs
Post by: CP5670 on December 17, 2005, 12:34:24 pm
Yeah, I've read about that several times. What is really interesting is this setup (http://www.tomshardware.com/2005/12/14/sneak_preview_of_the_nvidia_quad_gpu_setup/). ;7

Although with only 2000 cards manufactured and a price of $1000 per card, it's more of a novelty than anything practical. :p
Title: Re: Dual GPUs
Post by: ZmaN on December 18, 2005, 09:56:17 am
Yeah, I've read about that several times. What is really interesting is this setup (http://www.tomshardware.com/2005/12/14/sneak_preview_of_the_nvidia_quad_gpu_setup/). ;7

Although with only 2000 cards manufactured and a price of $1000 per card, it's more of a novelty than anything practical. :p

not too mention that each card needs its own power supply (well power adapter that connects to the ATX 12V Rail i think)...

A ripoff for years to come!
Title: Re: Dual GPUs
Post by: WMCoolmon on December 18, 2005, 03:27:41 pm
 :lol: :lol:

This is so absurd it's comedy. If they were cheaper, I'd probably try and buy one. :p