Tri-fire on a P67 board worth it?

SaViOr-

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So I was thinking about picking up a 3rd 6950 towards the end of the month in preparation for Battlefield 3 and had a few questions.

I read somewhere that eyefinity didn't work properly with a tri-fire setup. Has this issue been fixed or is it still there? I game at 5932x1080 w/ bezel comp.

Would I still see a noticeable performance increase going to tri-fire even though the third 6950 will only be running at 4x? The first 2 cards will run at 8x each and then the third would be running at 4x, which would also disable all other pci 1x slots.

Will my Power Supply be able to run 3 OC'd 6950s and my 2500k?

I really want to be able to run BF3 maxed out in Eyefinity with at least 2xAA and hopefully be able to have HBAO On with good framerate.

As always, any comments and/or suggestions are welcome. :)
 
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manofthem

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I'm not completely sure, but there's not much space between the 2nd and 3rd pcie slots on your mobo. Theres going to be no air flow between the cards, and considering it's already going to be running at 4x max, I doubt it would be worth spending the $200-250. At that resolution, it would really be good running at x16/16/8, or even x16/8/8.
 

Drheadbang

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Would it be possible for you to pickup an 6990 after selling the 6950? That's the only compromise I can see for running on a 16/8 and sticking with 2 slots.
 

samuelmorris

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As far as I recall, eyefinity on 24" monitors is fine with 3-card crossfire, it's only 30" eyefinity that used to have problems, and I'm not sure if it still does or not.
 

-Sn1PeR-

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I would wait and see if BF3 is any more demanding on the GPU than BC2. BC2 (as you probably know) flies in eyefinity with 2x 6950's.
 

SaViOr-

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I would wait and see if BF3 is any more demanding on the GPU than BC2. BC2 (as you probably know) flies in eyefinity with 2x 6950's.

Sadly I haven't gotten a chance to enjoy BC2 maxed out yet in Eyefinity :(. I'm experiencing that problem where the game will CTD if using anything other than LOW settings. This problem is supposedly fixed in the next patch for BC2 but who knows when Steam will approve it for release. I do average around 80-100fps running everything on low with 16xAF and DX11, which is kinda nice but the game looks like total crap. I'm okay with no HBAO as long as i can run high settings with 16xAF and maybe a little AA on BF3. Hopefully the BF3 Beta will be out soon so I can see how the game will run.

I just figured I'd post this up now so I know what my options are in case I'm not satisfied with how BF3 runs in Eyefinity with the CF 6950s.
 
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-Sn1PeR-

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If you play the Vietnam expansion you won't crash. Give that a shot and crank everything up.

I'm also starting to think that blaming steam for r11s delay is a PR stunt.
 

SaViOr-

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I'll try that when I get home from class this afternoon. I see your rig is similar to mine :). If you don't mind my asking, what settings do you run in Vietnam for AA/AF and HBAO On/Off & what kind of FPS do you get mainly min and avg? I'm assuming everything else is on High. That'll kind of give me a good starting ground for testing performance if you could help me out with that.
 

-Sn1PeR-

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I'll try that when I get home from class this afternoon. I see your rig is similar to mine :). If you don't mind my asking, what settings do you run in Vietnam for AA/AF and HBAO On/Off & what kind of FPS do you get mainly min and avg? I'm assuming everything else is on High. That'll kind of give me a good starting ground for testing performance if you could help me out with that.

BC2 Settings:
DX11, All High, 4x AA, 16x Aniso, HBAO Off
Averaging ~75 fps @ 6048x1080 in a full multiplayer game

I don't run a FPS monitoring utility due to that causing PB issues, but last I checked that was my framerate. That should give you a good starting point.
 

LEVESQUE

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As far as I recall, eyefinity on 24" monitors is fine with 3-card crossfire, it's only 30" eyefinity that used to have problems, and I'm not sure if it still does or not.

3X30'' Eyefinity is wortking fine, since that's what I'm using with my Quad-Fire 6990+6970+6970 set-up.

The ''problems'' you are talking about never really existed btw. It's a well known member posting here that said that the Crossfire bridge didn't had enough bandwith to do 3X30'' LCD with 3 or 4 AMD GPUs, but it was proven untrue. It was PEBKAC.

But since that guy did post that false information on 75 different forums (or more), the internet phenomena of ''copy and pasting'' did catch on fire, and everyone thaught it was true... because of 1 random guy.

But it's working fine.
 

samuelmorris

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You'll never get decent frame rate with just two 6950s playing BC2 at 5760x1080/3240x1920 with max detail, it's not a bug, it's just too demanding for that. Two HD6970s are just about enough for max HBAO but with 4xMSAA not 8x. Running 24" eyefinity3 is a good 52% more pixels than that, and obviously HD6950s are slightly slower cards.
 

FuzzyKittens

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What Kind of power supply you got? if you do plan on running 3 card your going to need 1200-1500w
 

SaViOr-

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BC2 Settings:
DX11, All High, 4x AA, 16x Aniso, HBAO Off
Averaging ~75 fps @ 6048x1080 in a full multiplayer game

I don't run a FPS monitoring utility due to that causing PB issues, but last I checked that was my framerate. That should give you a good starting point.

Just tried out Vietnam and it runs perfect! :D Played for a good 2 1/2hrs without crashes or issues. All High 4xAA 16xAF and was right around 75-85 in a full game of rush, trying to arm and disarm mcoms. Thanks for the info! Guess I'll just enjoy BC2: V until the BF3 beta is released :p

You'll never get decent frame rate with just two 6950s playing BC2 at 5760x1080/3240x1920 with max detail, it's not a bug, it's just too demanding for that. Two HD6970s are just about enough for max HBAO but with 4xMSAA not 8x. Running 24" eyefinity3 is a good 52% more pixels than that, and obviously HD6950s are slightly slower cards.

Not true. I can actually run BC2 at Max detail and 2/4xAA, but the game will CTD within 10 minutes of online play. Playing on medium 2xaa lets me play for about 30 min before CTD and playing on low I can get 2hrs+ in before I get a CTD. It's a known issue with Eyefinity/NV Surround setups that DICE is aware of and has been fixed in the patch that is going to be released next. :cool:
 

samuelmorris

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Sure you can play it, just at 40fps instead of 60. Fine for most, for me? Not really enough. And yeah I'm aware of the CTD issue. Irritating if Steam still haven't patched it.
 

arachn1d

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I have 2x 6950's (slightly over clocked) and I average 40-60fps on BC2 max settings (besides hbao).

I was thinking of a 3rd 6950 as well but now that I think of it, I don't think the mobo has any room for that. I think our best bet is next gen cards... or 2x 6900's? lol
 

samuelmorris

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Yeah I run with HBAO on, and with just 4.1 Megapixels versus the 6.2 of 1080p Eyefinity, two HD6970s can just manage a fluid 60-70fps with 4x MSAA. On my old HD4870X2 Quad crossfire setup, I had to leave HBAO and Anti-aliasing switched off entirely to get that sort of frame rate, even 2xAA without HBAO put me in the 40fps duldrums on several maps.
 

Ehren8879

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Didn;t read the other posts, but at this point the 6900's have bottomed out in terms of pricing. With the next gen available within four months or so, I'd have to say if you absolutely need more performance then go with a third now. However saving your money, unloading your current cards and investing in two of the next gen will be a better solution. Just my opinion.
 

Spree

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You'll never get decent frame rate with just two 6950s playing BC2 at 5760x1080/3240x1920 with max detail, it's not a bug, it's just too demanding for that. Two HD6970s are just about enough for max HBAO but with 4xMSAA not 8x. Running 24" eyefinity3 is a good 52% more pixels than that, and obviously HD6950s are slightly slower cards.

You can get great frames with 2 6950s all high IF if you have HBAO disabled. In fact you will have good frames if you do enable it but unfortunately it doesn't make the game feel smooth. That's in my experience anyway. My 6990 drives BC2 at 6000x1200 (5x1 eyefinity) all high with HBAO off very nicely. 80-100fps and feels good. Tri fire also works nice (6990 + 6970 at x16/x16).

I have 2x 6950's (slightly over clocked) and I average 40-60fps on BC2 max settings (besides hbao).

I was thinking of a 3rd 6950 as well but now that I think of it, I don't think the mobo has any room for that. I think our best bet is next gen cards... or 2x 6900's? lol

Those frames seem quite low for crossfired 6950s especially considering you have HBAO off. What resolution and what speed is your CPU clocked at? Would also be interesting to know if you measure the GPU usage with an app like afterburner as both GPUs should be maxing out. I get better frames than that at 11.5 megapixels (6000x1920) with a 6990.
 
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samuelmorris

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Well, that's what I meant by max detail - everything switched on. If you turn off HBAO, sure, it becomes much more playable - but it's also no longer max detail :p
When you say 6000x1200, do you mean 9600x1200?
 

Lord_Exodia

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So I was thinking about picking up a 3rd 6950 towards the end of the month in preparation for Battlefield 3

Wow I feel like this thread has gone astray. I could be wrong but although your motherboard has 3 full length pcie slots you can only SLi or Crossfire using the top 2 slots. 1 card runs at 16x 2 cards each run at 8x each and the 3rd slot can't be used for Multi GPU, perhaps PhysX

Here is the spec page of your motherboard form asus website

http://usa.asus.com/Motherboards/Intel_Socket_1155/P8P67_PRO_REV_31/#specifications

Here is what it says about multi gpu and expansion slots

Multi-GPU Support Supports NVIDIA® Quad-GPU SLI™ Technology
Supports AMD® Quad-GPU CrossFireX™ Technology
Expansion Slots 2 x PCIe 2.0 x16 (x16 or dual x8)
1 x PCIe 2.0 x16 (x4 mode, black) *1
2 x PCIe 2.0 x1
2 x PCI

MQFSBDmACxO8SrZM_500.jpg


To know for sure I'd call asus If I were you before you go on and get the 3rd card.

Digging even further I have a P8P67 Deluxe B3 revision and it also has the same slot layout and look at what it says for my expansion slots (specifically about the 3rd black slot)

PCIe 2.0 x16 [Black] (at x4 mode, compatible with PCIe x1 and x4 devices)

This is found on the spec page at Asus

http://usa.asus.com/Motherboards/Intel_Socket_1155/P8P67_DELUXE/#specifications

I'd hate to be the one to burst your bubble but getting a 3rd card isn't probably going to get you trifire.

However what you could do is get a 6990 and sell one of your 6950s and do trifire that way. Or if you hit the lotto get 2 6990 and sell your other 2 6950s for quadfire. Keep in mind both 6990s will only run in 8x mode. Not sure how that would impact Quad GPU more than a a single gpu in a slot but if it's the same I wouldn't worry because it's about a 1fps maybe 2fps difference on single gpu cards.
 
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Spree

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Well, that's what I meant by max detail - everything switched on. If you turn off HBAO, sure, it becomes much more playable - but it's also no longer max detail :p
When you say 6000x1200, do you mean 9600x1200?

Nope sorry, I actually meant 6000x1920 - the monitors are in portrait mode.
 

SaViOr-

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Well, back to my original questions..

Would tri-fire on my P8P67 Pro board be worth it since the card would only be running at 4x, would it even be possible to tri-fire on this board and would my TX850 be enough to drive my rig with a 3rd 6950?

I figured I should try and see if I can get answers to any of the above in here since this is mainly a video card question and I already have the thread up, but I'll ask about specific things in the motherboard and power supply sections of [H] if I can't get any definitive answers here.

Thanks for all who have posted so far. Appreciate it
 

Lord_Exodia

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Well, back to my original questions..

Would tri-fire on my P8P67 Pro board be worth it since the card would only be running at 4x, would it even be possible to tri-fire on this board

Read post #19 on page one toward the bottom.
 

Direfox

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Its hard to tell if its even possible to do, the board supports up to quad GPU's but the intent would be two dual GPU cards. Even if you could though, the bottom slot is going to choked badly....

From the mobo description-

*1: The PCIe x16_3 slot shares bandwidth with PCIe x1_1 slot, PCIe x1_2 slot, USB3_34 and ESATA12. The PCIe x16_3 runs at x1 mode by default for system resource optimization.(PCIe x1_2 will be disabled.)
*2: These SATA ports are for data hard drives only. ATAPI devices are not supported.

Thats sharing a lot of bandwidth through a tiny little hole.
 

SaViOr-

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Its hard to tell if its even possible to do, the board supports up to quad GPU's but the intent would be two dual GPU cards. Even if you could though, the bottom slot is going to choked badly....

From the mobo description-



Thats sharing a lot of bandwidth through a tiny little hole.

The part that confuses me is that if something is plugged into the bottom 16x slot, all the other pci-e 1x slots get disabled so its not sharing any bandwidth at all at that point. I just can't really find anything that definitively says yes or no to tri-fire on this board.

Lord_Exodia - I read your post, but it doesn't say that it won't work. All it says in the specs is that the bottom 16x slot runs at 4x mode if something is plugged in. I wish I could borrow a 6950 from someone to try it out before I go and spend the money on the 3rd card. That way i would know for sure lol
 

samuelmorris

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I think it should work, you will just be limited to 8x+4x+4x instead of 8x+8x, which is an obvious limitation with 3-way crossfire on P67. You won't be able to use the 1x slots or USB3/SATA3 either, but the USB/SATA you lose will still operate in USB2/SATA2 mode.
 

Lord_Exodia

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The part that confuses me is that if something is plugged into the bottom 16x slot, all the other pci-e 1x slots get disabled so its not sharing any bandwidth at all at that point. I just can't really find anything that definitively says yes or no to tri-fire on this board.

Lord_Exodia - I read your post, but it doesn't say that it won't work. All it says in the specs is that the bottom 16x slot runs at 4x mode if something is plugged in. I wish I could borrow a 6950 from someone to try it out before I go and spend the money on the 3rd card. That way i would know for sure lol

Just spoke to Asus to make sure, since I have a similar board to you and I would like to know for sure. They said the 3rd slot will not support a video card. It's specifically for "add in cards" They said, sound cards/ network cards, scsi, ssd controllers etc..

The motherboard isn't designed to use 3 cards in all 3 full length slots

For Tri SLi/CFX you need to use a dual GPU along with a single GPU

For Quad SLI/CFX you need to use 2 dual GPU's

The rep also went on saying that this is a limit of the P67 chipset as it's not a enthusiast class chipset. The models that can support 3 cards have an auxillary chipset e.g. NF200 such as the P67 Maximus boards.

So there you have it, confirmed by Asus 2 cards is your limit. BTW I asked about PhysX and they said it would not work to add a 3rd videocard so even a dedicated Physx GPU is a no go.

Think of that 3rd slot as an expansion slot that works for your sound card if your using both X16 slots for SLi or crossfire. Since the X1 slots are disabled you need at least one more slot besides for video to accomodate a extra card. That slot is it.
 

SaViOr-

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Just spoke to Asus to make sure, since I have a similar board to you and I would like to know for sure. They said the 3rd slot will not support a video card. It's specifically for "add in cards" They said, sound cards/ network cards, scsi, ssd controllers etc..

The motherboard isn't designed to use 3 cards in all 3 full length slots

For Tri SLi/CFX you need to use a dual GPU along with a single GPU

For Quad SLI/CFX you need to use 2 dual GPU's

The rep also went on saying that this is a limit of the P67 chipset as it's not a enthusiast class chipset. The models that can support 3 cards have an auxillary chipset e.g. NF200 such as the P67 Maximus boards.

So there you have it, confirmed by Asus 2 cards is your limit. BTW I asked about PhysX and they said it would not work to add a 3rd videocard so even a dedicated Physx GPU is a no go.

Think of that 3rd slot as an expansion slot that works for your sound card if your using both X16 slots for SLi or crossfire. Since the X1 slots are disabled you need at least one more slot besides for video to accomodate a extra card. That slot is it.

Thank you! I was actually going to call myself after class today, but you beat me to it lol :p. Guess I'll have to invest in a 6990 if some OT kicks in soon here or just settle for a little less eye candy until new gen of cards comes out & see what they have to offer.
 

samuelmorris

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That smells of unnecessary BIOS trickery to me. Pretty sure there's nothing in the P67 spec that prevents three graphics cards being run off the chipset, the latter two will just get starved of bandwidth.
 

Lord_Exodia

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Thank you! I was actually going to call myself after class today, but you beat me to it lol :p. Guess I'll have to invest in a 6990 if some OT kicks in soon here or just settle for a little less eye candy until new gen of cards comes out & see what they have to offer.

I have the same upgrade path too, and to be honest I grabbed this sandy bridge build as something to hold me off until Bulldozer or Ivy Bridge at the most. I might be upgrading very soon. Also these 2 6950s will be going in favor of Tri SLi or Trifire of 7000 or Kepler watercooled. I expected bulldoxer sooner though, and now I'm starting to think it's not going to be all that I thought it might have been. I'll run everything I can with my dual 6970s (6950s unlocked & overclocked) and by the time they feel too slow I'll be on new hardware anyway.

That smells of unnecessary BIOS trickery to me. Pretty sure there's nothing in the P67 spec that prevents three graphics cards being run off the chipset, the latter two will just get starved of bandwidth.

I thought the same thing and I think it was wishful hoping since I have the same board or at least similar. It actually is a limitation of the chipset. I believe at most 20 pcie lanes can work at once. See the diagram below, notice it's 1 16 lane graphics or 2 8 lane graphics.

Once 2 graphics cards are filled, the 2 1x slots are disabled and you can use the last full length slot for up to a 4 lane expansion card. Not graphics or PHysX however.

P67_block-diagram_450x408.jpg
 
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