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SquireSCA
12-11-05, 09:48 PM
Bekow in my sig are my current specs. The Gigabyte board is great, but I cannot overclock the CPU worth a damn. I get maybe 100Mhz more out of it and then it craps out. Tried lowering HTT to 4x. increased various voltages, lowered the memory divider to eliminate that, no dice.

I have a hard time believing that the chip will not overclock. At stock, it sits at 26C idle and tops out at 38C with Prime95 and Sisoft Sandra CPU Burn-In running at the same time while I surf the net and download pr0n from KazaaLite. So heat is not the issue here.

I think that while the Gigabyte boards are great quality and lots of features, they are sometimes not the best overclockers.

So I am considering a new mobo tomorrow. I will look at the Abit, Asus and DFI offerings at the local Fry's. If I am getting a new mobo anyway, I might as well get an SLI board, right?

My question is, is it worth picking up the second card? I play games at 1680x1050 whenever possible, and while it works fine, I am wondering how much better things would look if I cranked up the FSAA to 6x and stuff.

Money is not a concern, but making sure that I get some sort of tangible benefit for my money, is.

I also do not want to have to mess around with profiles and stuff. Basically I do not want to have to tinker to get common games to run properly. I play primarily:

FEAR
Serious Sam 2
Far Cry
RTCW
HALO
Painkiller Gold Edition
UT2004
Quake4
Doom3

So, is this worth it, or should I just get a better mobo for overclocking and keep a single GTX for now?

a12ctic
12-11-05, 09:52 PM
im fine with a 6600GT, plays all the games i want it to on medium or high settings so i really dont see a need for sli, i gues it looks cool and you get beter benchmarks, if i were you i would stay away though.... Voodoo SLI failed for a reson, i dont see why it will last any longer this time, Who wants to pay double for a 30% performance boost?

SquireSCA
12-11-05, 09:53 PM
im fine with a 6600GT, plays all the games i want it to on medium or high settings so i really dont see a need for sli, i gues it looks cool and you get beter benchmarks, if i were you i would stay away though.... Voodoo SLI failed for a reson, i dont see why it will last any longer this time, Who wants to pay double for a 30% performance boost?

Hmmm... Interesting point. If not SLI, is there a particular mobo that you would recommend?

a12ctic
12-11-05, 09:57 PM
I have a msi neo4 -f, it gets the job done... If i had the money id go with DFI or ASUS though....

OWA
12-11-05, 09:58 PM
It really helps with high res gaming or if you like to run with max settings but a lot of the time you end up needing to play with profiles some. Although, with most of the games you listed, things should just work (that is, it'll probably be mostly plug and play).

OWA
12-11-05, 09:59 PM
Hmmm... Interesting point. If not SLI, is there a particular mobo that you would recommend?
Yeah, but you have to consider he thinks a 17" monitor and med settings are more than enough. If you're okay with running lower settings or resolution, then yeah, SLI is a waste. I'd think it would help quite a bit with your native resolution of 1680x1050.

a12ctic
12-11-05, 10:03 PM
i also have this to say

SLI 7800GTX is prety much the same performance as the 7800GTX 512mb card....

2 brand new cards already outdated by a single card...? Really isnt worth it in my opinion by the time ups gets you your second card it will already be outdated...

SquireSCA
12-11-05, 10:04 PM
i also have this to say

SLI 7800GTX is prety much the same performance as the 7800GTX 512mb card....

2 brand new cards already outdated by a single card...? Really isnt worth it in my opinion by the time ups gets you your second card it will already be outdated...

The 512MB card is faster than two 256mb cards in SLI? How is that?

OWA
12-11-05, 10:11 PM
Here is an example in FEAR:

SLI 1680x1050 4xAA/16xAF HQ, TAA:SS, GAA:On
32/60/194 (0%/2%/98%)

Single GPU 1680x1050 4xAA/16xAF HQ, TAA:SS, GAA:On
20/33/72 (18%/60%/22%)

saturnotaku
12-11-05, 10:11 PM
The 512MB card is faster than two 256mb cards in SLI? How is that?

Higher clock speeds, plus you actually have a full 512 MB framebuffer to work off of.

nV`andrew
12-11-05, 10:12 PM
the clocks speeds are higher and it offers more memory in a single card. i think he means value. You get more out of the 512mb for its money than you do with the 2 256mb's that cost more. Plus, you are also paying more for that SLi mobo. If budget isn't a factor, simply buy an SLi mobo, the Asus A8N SLi premium is nice, and get another 256 meg gtx which will help u out with those resolutions. Or get an asus or dfi mobo and sell your gtx and get the 512mb higher-clocked GTX.


(xmassign)

SquireSCA
12-11-05, 10:16 PM
Interesting... Tht 512mb looks sweet, but man it is a power hog, but then again, so is a pair of GTX cards. I am wondering i my Neopower 480W is up t the task?

As far as money goes, I already have the GTX. I guess I could sell it and get the faster card and so then I would only be paying the price of the new card minus a few hundred I could get for this card.

Decisions, decisions.

Perhaps I will just get a better SLI mobo and see if I can get this CPU up into the 2.4Ghz range, and then later add a second card when the price comes down and new games actually need more power...

OWA
12-11-05, 10:20 PM
Doom 3 (since Q4 doesn't have a built-in benchmark)

Single 1680x1050 4xAA/8xAF HQ
73.9

SLI 1680x1050 4xAA/8xAF HQ
117.3

It actually depends on the game. Far Cry doesn't show much of an improvement. D3, Q4, Painkiller, and FEAR show a big improvement but you also have to factor in that 73.9fps (for example in D3) is still good enough. I'm not sure about the rest since I haven't really tested them a lot.

Edit: Also, the 256s show the same trends as the 512s, the 256s pretty much double the framerate a lot of time in FEAR as well (for example).

SquireSCA
12-11-05, 10:28 PM
Well, this is good information. I think that tomorrow I will go and get a better mobo and see what I can get out of this CPU, and I will enjoy my GTX for now. In the next few months, when prices start to come down, I will make a decision to either add a second GTX, or sell my current one and get the faster 512mb card.

But for now, keep those mobo recommendations coming! I want to keep it under $200.

phide
12-12-05, 02:39 AM
The DFI boards are very solid. They just released a new version, in fact, of their SLI-D(R) series boards, though I don't feel it justifies the higher price tag.

A DFI SLI board can be had for roughly $170.

And for reference, the GTX 512 uses about 10 watts more under load than the GTX 256. Two GTX 256s use almost twice as much as a single GTX 256, or about 200-210 watts. From a pure single card performance, cost, noise level, power load and compatibility perspective, the GTX 512 is (currently) unbeatable.

shoes
12-12-05, 02:53 AM
SLI is good if you can afford it and you have a large high native res LCD. Another benefit is that if you go SLI right away, instead of selling the cards a year later you can just divi them out to other rigs you have to upgrade them (or your G/F ot wife ir she games). I have a good friend that had SLI'ed 6800 Ultras - he just sold one of them, and gave the other to his G/F's box, and bought a 512 GTX (No SLI this time though .. yet anyway). I was going to go SLI but i truely like gaming on my CRT over any LCD - and that gives me more than one resolution to game with (so i can lower it if needed) and that also means i don't need SLI to get great frame rates in games. If i wanted to game on a 23-24" LCD then i would go SLI for sure.

rewt
12-12-05, 02:55 AM
Higher clock speeds, plus you actually have a full 512 MB framebuffer to work off of.

How much framebuffer would the two 256MB cards have?

I think, by using two cards in SLI you at least double the memory bus width. So two cards having 256-bit memory would then have 512-bit memory bus when used together. At least thats what I've read.

Still not sure about the framebuffer though. All I know is that my two 6600GTs with 128MB each can out-bench (by ~1,500 points in 3dmark05) than most 6800GT/Ultras out there that have 256MB framebuffer.

1,500 points higher in 3dmark05, considering;

6600GT = 8 pixel pipes, 3 vertex shader, 500 Mhz core, 1000 Mhz 128MB 128-bit DDR3

6800GT/Ultra = 16 pixel pipes, 6 vertex shader, 400+ Mhz core, 1000+ Mhz 256MB 256-bit DDR3

Plus I noticed that my dual 6600GT 128MB are much smoother than 128MB 6800NU in games when textures are set at maximum (i.e. Battlefield 2)

MUYA
12-12-05, 03:13 AM
The contents on the memory of both cards are mirrored, so if you are using 2x 256mb cards for SLI, you would still be limited to 256mb each card. Because both frame buffers are mirrored, the memory bus is still 256bit. SLi seem smoother because the minimum fps maybe higher :D

rewt
12-12-05, 03:16 AM
Then how is the minimum fps higher? I still don't get how 2 6600 GTs can out score 6800 Ultra by 1500 points by having only 128MB framebuffer and 128-bit memory bus.

MUYA
12-12-05, 03:23 AM
U said your SLI has smoother gameplay than a 6800NU. I speculated thats coz the minimum FPS is higher than on a single card. How else can you explain that?
3dmark2k5 is more vertex shading limited and IIRC it is not totally overally reliant on framebuffer memory size. Therefore, you have 6 VS units in SLI with the 6600Gts running at a core clock of 500 mhz each. The 6800U has 6 VS units running at 400 MHz. Maybe thats why? However, maybe if you turn AA and AF on, the 6800U will win because, the 256 bit memory bus will come more into play then.

rewt
12-12-05, 03:24 AM
Is it like having an 1000 MHz 8 pixel pipeline, 3 vertex shader GPU?

If so then why on 128MB card is BF2 so jerky/jittery when details are set maximum. And on 2 6600GTs with the same amount of framebuffer there is absolutely no jerking what-so-ever.

Lfctony
12-12-05, 03:25 AM
Pure fillrate and VS power, but that's where the advantage stops I think. The memory and the limited BW don't come into play in the standard 3DM test. In AA/AF situations the 6800U would have the advantage.

MUYA
12-12-05, 03:31 AM
Thats because the contents are mirrored on both framebuffers of the card. While one works on one frame, or half the frame the other works on the otehr half or other frame. Ideally all data that is needed for that scene or alternate frame is onboard the vid card framebuffer. Therefore, in situations like those, the framebuffer doesn't haven't to reach into main system memory to fetch texture data and rendering of that frame is faster and consequent ones that use the same data. ie good use of data. ie teh frame is being rendered that quicker. Thats the only thing I can think off. Whereas in a single card config, a scene thats needs to be rendered will take a longer time.

MUYA
12-12-05, 03:33 AM
Is it like having an 1000 MHz 8 pixel pipeline, 3 vertex shader GPU?

No you get theoretically, a 500 Mhz core 16 pixel pipeline, 6 VS GPU....

rewt
12-12-05, 03:39 AM
Thanks guys for your explanations. :)

I think overall SLI has worked out pretty well for me.

I wouldn't recommend going to spend thousands of dollars on an SLI setup however (sorry nVidia). It can be a pain at times because some games don't fully support SLI, and movies play funky if I don't enable vsync. But for the price, I can't complain. $370 for a NF4 mobo, 2 eVGA 6600GTs, and Venice 3000+ CPU.