QX6700 - possible bottleneck for 8800GTX SLI?

[terentenet]

So here's the question. Does a QX6700 @ 3GHz bottleneck 2 8800GTX running in SLI? I don't know what to do to get more performance. Overclock the CPU? Or volt-mod the video cards and give them a boost?

I believe I can easily overclock the CPU, it's being cooled with a Vapochill LS unit.
I can also volt mod and overclock the video cards, they are water cooled.

So, what am I to do?
This is how the system looks so far. I will be taken apart this week, some fans need to be exchanged. Need higher CFM.

http://www.crazypc.ro/forum/attachment.php?attachmentid=20831&d=1177575193

Note: I will run my games at 2560x1600. At that resolution, where is the bottleneck?

 

[m21s]

Ok so you are done bragging...

Do you honestly think your going to be bottlenecked?

Seriously?

 

[terentenet]

No, it's not about being bottlenecked and I'm not bragging. That PC is a factory, consumes watts like a factory and sounds like a factory. It went too far.
But; if I want more performance, where will I see most gains? by overclocking the CPU? Or volt modding the video cards?

 

[m21s]

Your not going to need more performance.

That system will run anything you throw at it.

But if you must...For games OC the video cards, and for anything else your doing besides gaming (video encoding and what not) OC the CPU.

 

[terentenet]

2560x1600 will not pose a problem for the video cards? It scares the s### out of me, it's 4MP of image. I never ran the 8800gtxs' on this monitor. System is not finished yet. They ran everything @ max when using 1680x1050, but that's merely 1.7MP.

 

[m21s]

1 GTX can run that ressolution, plenty of current benchmarks can show this.

This is why I question your thoughts....lol

That system is a MONSTER!

 

[happy medium]

Originally posted by: terentenet
So here's the question. Does a QX6700 @ 3GHz bottleneck 2 8800GTX running in SLI? I don't know what to do to get more performance. Overclock the CPU? Or volt-mod the video cards and give them a boost?

I believe I can easily overclock the CPU, it's being cooled with a Vapochill LS unit.
I can also volt mod and overclock the video cards, they are water cooled.

So, what am I to do?
This is how the system looks so far. I will be taken apart this week, some fans need to be exchanged. Need higher CFM.

http://www.crazypc.ro/forum/attachment.php?attachmentid=20831&d=1177575193

Note: I will run my games at 2560x1600. At that resolution, where is the bottleneck?[/q]

At that resolution it's your cards. Volt mod and overclock if they are water cooled.
You should be able to get 3.4 ghz from that cpu. If your gonna do it do it right.
Games like FEAR, oblivion,Stalker at max res and aa/af will beat them cards to death.

 

[terentenet]

Thanks, glad you like it. I'm kinda leary about the SOUND of it. It buzzes so hard you can hear it from the next room. I'm going to have to get used to it.

@happy medium
That's what I'm affraid of. 8800GTX is a very powerfull card, but that's 4MP of image and it's not a joke even for the 8800GTX. SLI will help a little, but it will not make a night and day difference.

 

[happy medium]

In reallity you might not need aa/af with that high a resolution but you did spend thousands of dollars on the puppy..........You would think it would run anything. I hope your prepared to sell and buy cards every year or so to keep up with that resolution. Good luck .

 

[Chaotic42]

Get Supreme Commander on there. I'd love to see your benchmarks at 2560x1600.

 

[Fallen Kell]

You need to rethink your cooling if you can hear it in another room. With 120mm fans and water cooling there is no reason in the world that it should make that much noise unless it is really poorly designed. You should have an external water tank and an external radiator (or even twin radiators) to cool the heat. That should cut your noise down dramatically.

 

[terentenet]

Originally posted by: Chaotic42
Get Supreme Commander on there. I'd love to see your benchmarks at 2560x1600.

I'm affraid
Give me one week so the system will be ready and I will post benches.

Originally posted by: happy medium
In reallity you might not need aa/af with that high a resolution but you did spend thousands of dollars on the puppy..........You would think it would run anything. I hope your prepared to sell and buy cards every year or so to keep up with that resolution. Good luck .

Correct. I'm eagerly waiting for 8900GTX... and waterblocks for it... and another voltmod?

Originally posted by: Fallen Kell
You need to rethink your cooling if you can hear it in another room. With 120mm fans and water cooling there is no reason in the world that it should make that much noise unless it is really poorly designed. You should have an external water tank and an external radiator (or even twin radiators) to cool the heat. That should cut your noise down dramatically.

Nah, I was exagerating. It's not THAT loud, but louder than average W-C systems. The LS alone makes a sound of its own with 2 120x120x38 high rpm fans.
I have 2 water loops in that. One for the video cards alone, 2nd for the motherboard and ram.

 

[Chaotic42]

Originally posted by: terentenet

I'm affraid
Give me one week so the system will be ready and I will post benches.

My E6600 with 4GB of memory and a 7800GTX gets a minimum of 3fps at 1920x1200. It's a rough game.

 

[terentenet]

Originally posted by: Chaotic42

Originally posted by: terentenet

I'm affraid
Give me one week so the system will be ready and I will post benches.

My E6600 with 4GB of memory and a 7800GTX gets a minimum of 3fps at 1920x1200. It's a rough game.

AA/AF?

 

[happy medium]

I just noticed your rig has only 2 gigs of ram. For those resolutions mabe a gig more is better?

 

[nitromullet]

Originally posted by: happy medium
In reallity you might not need aa/af with that high a resolution but you did spend thousands of dollars on the puppy..........You would think it would run anything. I hope your prepared to sell and buy cards every year or so to keep up with that resolution. Good luck .

That is completely incorrect... The resolution is directly proportional to the size of the screen on LCDs. The pixel pitch is the same on a 20" 1680x1050 LCD as it is on a 30" 2560x1600 LCD, so the need for AA is exactly the same. The only time you theory holds true is if different resolutions are compared on the same size screen.

In regards to the OP's original question, I would assume that even SLIed GTXes would be the bottleneck in most situations, and if it isn't I'd suggest cranking up the eye candy. Either way it is somehow irrelevant, since its not really possible right now to upgrade anything on your system... if you did find a 'bottleneck', what could you really do about it?

...that is a totally insane build. Just curious though, was there a reason that you opted against covering those unsightly optical drives with drive bezels?

 

[MADMAX23]

What can bottleneck your system's performance is your FSB speed....QX6700s at stock speed (2.66Ghz) need at least a FSB speed of 1333Mhz (333 FSB x 4) not to get noticeably bottlenecked.

Even with that FSB speed, a higher FSB speed like 1600 Mhz (400 FSB x4) for stock speed (well, 381 FSB x 7 = 2.667 Ghz, and so, 381x4 = 1524 FSB), is still recommended.

Higher FSB speeds like 1800 Mhz (450 FSB) or 2000Mhz (500FSB) are recommended if you are overclocking the Quady.

Remember you're dealing with 4 CPUs, not only 1 or 2.

Also note that when you are using only 2 cores simultaneously, you'll have enough bandwidth with a FSB speed of 1066 Mhz or 1333 Mhz, but when an application is stressing the 4 cores at the same time, 1333 Mhz will be the minimum FSB bandwidth your system must have....being 1600 Mhz or higher speeds recommended.

About your 2 GTX: Don't worry, your QUADY can handle them...2 cores for each card...it's enough. And again, the bottleneck is in the motherboard FSB speed/bandwidth so stress the hell out of it.

Edit: That monster of a system and only 2 Gb of Ram.....get another 2 Gb, you'll see the difference, I promise. I build High-end systems...and no one gets less than 4 Gb of Ram.

 

[Chaotic42]

Originally posted by: terentenet

Originally posted by: Chaotic42

Originally posted by: terentenet

I'm affraid
Give me one week so the system will be ready and I will post benches.

My E6600 with 4GB of memory and a 7800GTX gets a minimum of 3fps at 1920x1200. It's a rough game.

AA/AF?

Hah!

No. I think I've got most of the settings on medium. Shadows are on low, I believe.

 

[terentenet]

Ok, each at a time and thank you for your advices. I think I will have the volt mod and try to reach 680-700 for the core and 1100 (2200) for the memory.

@happy medium
4Gb Team Xtreem 1200MHz 5-5-5-15 are on the way. I will also have them watercooled with MIPS Ram Freezer 4.

@nitromullet
If there is a bottleneck, hopefully I can overclock to overcome it or ameliorate it at least.
Final build will have drive bezels for both Plextors. I allready have the bezels, just not mounted them yet.

@MADMAX23
1600 or 1800 FSB is also my thought. The motherboard is a EVGA 680i A1 rev. with factory mounted waterblocks on the SB, NB and Mosfets. Namely, EVGA 680i "The Black Pearl". It should overclock the quad's FSB nicely.
4Gb Team Xtreem is on the way.

@Chaotic42
I think I should have around 10-15FPS with max settings at 2560x1600. Not an assesment, just a thought. Any correction?

 

[JAG87]

dude I have the same config as you. i can honestly tell you, apart from call of duty 2, fear, and graw, there is nothing else that brings this system below 60 fps.

I run everything 2560x1600 with 4x AA and 16x AF. silky smooth. QX6700 @ 3.2 ghz with 8800 GTX in SLI. I have also tried more AA, and I can assure, you can run 8x AA and even 16x AA with no problem. 8x QAA and 16x QAA really bring the system to its knees.

my tips to you so you dont waste time (Ive done plenty of testing, had the system since november 2006):

- if you are thinking about more ram, think again. Stick to XP for your games, and XP can only do 2GB. forget the vista + 4GB ram plan for now. save it for later.

- FSB makes little or no difference at all. whether you run 1066, 1333, 1600, 2000, your gains will be so minimal, while you will cook your motherboard for no reason. there are gains, yes, but they are not worth the increase in voltages. So dont worry so much about FSB, and use that unlocked multiplier you got there. best to keep fsb at 1066 and stock volts on the chipsets, and to go up with multipliers. with a vapo LS, a realistic goal is 3.73 GHz (266x14) with 1.5V. Personally I would not go much above 1.5V, or the heat load becomes too much for the LS to handle.

- keep the video cards at stock. dont over estimate your watercooling, it will keep the cards cooler, but if you OC you will risk seeing artifacts and wasting a whole bunch of time figuring out correct clock speeds. remember, with the 8800s there are set core clock speeds at which the shader clock changes. its not just a simple core/mem overclock. once again, the from overclocking are so minimal, they are not worth the time and hassle.


thats all I can help you with. Im at 3.2 on air with 2 stock GTXs. with your vapo LS you should be able to hit 3.73 easy, while your watercooling will keep everything else fresh. nice rig dude congrats!

 

[TBSN]

Wow, that build IS insane. One thought about the possible NOISE problems: You can get sound-proof computer enclosures that basically look like a small cabinet with a glass window that the whole computer case goes into. They are generally used for systems that are used when silence is needed, like in a video editing suite or with studio pro-tools rigs. I think that one of those might be a good investment. (I mean you've gone all-out for all of the rest of the hardware, why not go all the way?) I see if I can find a link to what I'm talking about...

EDIT: HERE is an example of the kind of thing I'm talking about...

 

[MADMAX23]

JAG87, you are wrong, XP and VISTA 32 bit can handle up to 4 Gb of Ram, but will never use the 4gb effectively, only up to 3.5Gb will be used depending on your system's hardware.

Yesterday I built a system with a QX6700, a 8800GTX and 4 Gb of Ram...XP 32 bit used effectively 3 Gb of Ram, the Gb left was used by Windows for PCI resource allocation....it's a known issue with Windows 32 bit OSes.

And higher FSB speeds/ bandwidth do make a difference in overall system responsiveness/performance. For 1600 Mhz or 1800Mhz you don't need to supervolt the NB, JAG87...nowadays those FSB speeds are pretty easy to reach with a minor voltage increase...and on air.

 

[terentenet]

TBSN, thanks mate. I will wait the final build and see if I can handle the sound. If it's horrific and I can't take it, I will figure a way out of it. Until then, I was thinking I could use some sound insulation material for the inside of the case? Or at least I could try to.
It's going to be a mess in there, regardless of the wire management. There are just TOO MANY wires. Can't hide them all even if you want to.

Jag, Madmax, that's on old argue. High FSB will show it's strength in memory intensive tasks. As far as CPU power alone, FSB doesn't matter; CPU speed is all.
But. CPU speed AND high FSB, with high memory speed and good timings, will gain FPS when the CPU needs to fetch info from the RAM.

4Gb RAM is to help me futureproof the PC. I agree 2Gb is enough nowdays, but what about when Crysis and Alan Wake will be here? Will 2Gb handle the job?

 

[JAG87]

Originally posted by: MADMAX23
JAG87, you are wrong, XP and VISTA 32 bit can handle up to 4 Gb of Ram, but will never use the 4gb effectively, only up to 3.5Gb will be used depending on your system's hardware.

Yesterday I built a system with a QX6700, a 8800GTX and 4 Gb of Ram...XP 32 bit used effectively 3 Gb of Ram, the Gb left was used by Windows for PCI resource allocation....it's a known issue with Windows 32 bit OSes.

And higher FSB speeds/ bandwidth do make a difference in overall system responsiveness/performance. For 1600 Mhz or 1800Mhz you don't need to supervolt the NB, JAG87...nowadays those FSB speeds are pretty easy to reach with a minor voltage increase...and on air.

yes, yes, point is 4gb is useless with a 32bit OS. windows will not assign more then 2GB to any running application. it will cause more problems then gains. plus its very hard to do 4GB with 2 dimms, there are not a lot of kits like that and they cost a fortune. 4 dimms will certainly not run as smooth as 2 (latency and command rate wise). thats why im saying wait for now, in the future vista will have better performance, and 4GB kits will be more common.

and higher FSB speeds improve nothing. yes you dont need to supervolt the NB, but why overvolt it at all? for what 2 more fps? comon be realistic, were not talking about how fast we can make super pi run here. normal everyday applications see no benefit at all.

 

[JAG87]

Originally posted by: terentenet

4Gb RAM is to help me futureproof the PC. I agree 2Gb is enough nowdays, but what about when Crysis and Alan Wake will be here? Will 2Gb handle the job?

those 2 games will only run on vista (unless the dx10 for xp magic happens).
thats when you make the switch to 4GB. when applications like that come out that require to update your OS. thats when you buy a 4GB kit (and hopefully it will be cheaper then they are now).