Help powering too many cards.

[dark2099]

So I am getting a 3870x2 from DD and have 2x3870's that I will be attempting to use in quadfire. Basically I want to know if my PSU will be able to support all those cards plus the rest of the stuff in my specs (mobo and ram will be different). Link to the PSU below.

http://www.newegg.com/Product/Product.aspx?Item=N82E16817256020

[erocker]

I don't think you'll have any problems with power. I am curious to how to set up the crossfire bridges correctly.

[dark2099]

I don't think you'll have any problems with power. I am curious to how to set up the crossfire bridges correctly.

Good point. Couldn't I have a bridge from the 3870x2 to one 3870 and then a bridge between the two 3870s?

[Paulieg]

Dark, you should be alright. My question is, wtf you trying to do that would need 3x 3870x2? :wtf: Holy crap!

[Castiel]

First you have to make sure that your cards are exactly alike. I'm not for sure if you can QuadFire them. But your PSU looks fine to do that.

[dark2099]

First you have to make sure that your cards are exactly alike. I'm not for sure if you can QuadFire them. But your PSU looks fine to do that.

What do you mean exactly alike, the two 3870's are from visiontek, the 3870x2 will be from sapphire.

Dark, you should be alright. My question is, wtf you trying to do that would need 3x 3870x2? :wtf: Holy crap!

It will be 3 cards, 1 3870x2 and 2 plain 3870s.

[erocker]

Good point. Couldn't I have a bridge from the 3870x2 to one 3870 and then a bridge between the two 3870s?

Yeah, that's all you can do with the single connector on the X2. Really the extra 3870 may end up just sucking up more power than give you more performance.

[Castiel]

All cards are made different by different companies. If you have several different cards they wont respond to each other.

[dark2099]

Well come sometime next week I think we will have this answer.

[dark2099]

All cards are made different by different companies. If you have several different cards they wont respond to each other.

So are you saying that they won't all work together?

[DanishDevil]

Quadfire gains are still worth it.

Connections go:

3870x2
|_|
3870
_ |_|
3870

So one going from the x2 to the second card, and one connecting the last two 3870s.

Stand by for a full load wattage estimate.

The cards will work together. Crossfire is 2 cards. They should be similar. Different brands are fine.

Anything over 2GPUs is CrossfireX, and you can mix and match clocks (like you will with this setup)

[DanishDevil]

E8500 @ 4.5GHz 1.5v, 4 HDD's, 4 sticks of DDR3, 10 120mm fans, 3870x2, dual 3870s comes out to 813W at full load. You're fine.

[Castiel]

Quadfire gains are still worth it.

Connections go:

3870x2
|_|
3870
_ |_|
3870

So one going from the x2 to the second card, and one connecting the last two 3870s.

Stand by for a full load wattage estimate.

The cards will work together. Crossfire is 2 cards. They should be similar. Different brands are fine.

Anything over 2GPUs is CrossfireX, and you can mix and match clocks (like you will with this setup)

So is the same cards being needed is only for SLI?

[DanishDevil]

I'm not completely sure. I know you can't mix and match models like Crossfire X can. You can crossfire a 3870x2 with a 3870 and a 3850 if you like. I know that SLI needs the same model. Not sure if brand matters or not.

nVidia beat ATi to the multi-card game, but ATi has come a long way and surpassed nVidia since then.

You can also run Crossfire(x) on any board with multiple x16 slots, while SLI only runs on boards with an nVidia chip on it. Crossfire is completely software-driven.

[Castiel]

Ok, in SLI you have to have exactly the same cards. But for Crossfire you don't have to have the same brands but same models.

[dark2099]

Yay, means I hope to be putting up some nice benches. ::cool:

[JrRacinFan]

I hope you got Vista ready, dark2099. Only way you will be able to setup the drivers properly. :)

Good luck with the CrossfireX build.

[dark2099]

Yea, might use all 4GB of ram I am getting when doing benches.

[JrRacinFan]

No, not even that, the only way you can use CrossfireX with more than 2 GPU's is with Vista (32 or 64 bit).

[dark2099]

I am just saying that I would pull the 2GB ram out from the back up rig to throw in the main rig for benching so it has 4GB, if it will really help much.

[DanishDevil]

Actually, I heard a rumor that Cat 8.5's support XP CFX now...

[dark2099]

I think fit was the person who noticed that. But I will be running Vista for the sole purpose of Vantage.

[DanishDevil]

You should be good to go then!

[dark2099]

Almost, need the parts.

[DanishDevil]

Well duh...

[dark2099]

Right, I sometimes like to state the obvious.

[DanishDevil]

Then I will as well...PP me! :D

[cdawall]

Ok, in SLI you have to have exactly the same cards. But for Crossfire you don't have to have the same brands but same models.

not even you can xfire 3850s and 3870s

[DanishDevil]

http://game.amd.com/us-en/content/images/crossfirex/CF_combo_chart_Dec07.jpg

^^ Nuff said.

[dark2099]

Then I will as well...PP me! :D

Then sell my DFI.

[DanishDevil]

No. You sell mine first :D

[dark2099]

It's going to JR most likely.

[newtekie1]

I'm not completely sure. I know you can't mix and match models like Crossfire X can. You can crossfire a 3870x2 with a 3870 and a 3850 if you like. I know that SLI needs the same model. Not sure if brand matters or not.

nVidia beat ATi to the multi-card game, but ATi has come a long way and surpassed nVidia since then.

You can also run Crossfire(x) on any board with multiple x16 slots, while SLI only runs on boards with an nVidia chip on it. Crossfire is completely software-driven.

That isn't true. You can only run Crossfire and CrossfireX on Intel and AMD chipsets. It will not work on an nVidia chipset. Both technologies are entirely software driven, and really only need a motherboard with multiple PCi-E slots. However, both companies have locked down their drivers to only work with certain chipsets. I hate it. I also wish nVidia would allow you to mix and match models as long as they were the same core like ATi does. IMO, nVidia really need to loosen some of their restrictions on SLI. There should be nothing stopping people from SLIing a 9800GTX and a 8800GTS 512MB. I understand on some of the cards where the core is cut down or the bus width is different, but on cards were the core is identical SLI shouldn't be a problem.

[DanishDevil]

Talk to fitseries3. He's seen it done.

nVidia is working on Hybrid SLI. ATi just beat them to it.

[newtekie1]

Talk to fitseries3. He's run Crossfire on a 790i.

nVidia is working on Hybrid SLI. ATi just beat them to it.

I'm sure there is a way, it just isn't officially supported, just like running SLI was possible with older hacked drivers on Intel and AMD chipsets.

[DanishDevil]

Nvm he hasn't done it himself. He's seen it done.

The point I'm making is, SLI needs a chip from nvidia themselves on the board. ATi does not.

[JrRacinFan]

Ok, DD, I need to say this. What about my board that came with an SLi bridge? It does 6/7 series through hacked drivers. :p

**whispers** Sorry I just had to ..... :)

[DanishDevil]

I say great! Someone found a way to mod the drivers. I really hope that nVidia comes out with hybrid SLI soon, too. More competition for ATi.

[JrRacinFan]

LMAO, but they are old drivers and Geforce 8's will never be supported. That's the go-getter. :p

[newtekie1]

Nvm he hasn't done it himself. He's seen it done.

The point I'm making is, SLI needs a chip from nvidia themselves on the board. ATi does not.

And the point I'm trying to make is that the chip on the board isn't actually needed for SLI to work, nVidia just locks their drivers to require it. It is stupid, I know, but they do it. Probably so they will sell more of their own product.

[DanishDevil]

I agree. I'm sure someone will come out with hacked drivers eventually, and then they will have to make it hardware based if they get too popular.

Just imagine - proprietary PCI-Express lanes...:shadedshu