Low Profile cards + SLI or Crossfire?

QueBert

Lifer
Jan 6, 2002
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In a few months I'm going to build a HTPC with a low profile case. I do like to game and know that the selection of low profile cards isn't great, and the best ones are well below the performance of even last generations cards. I Googled this and saw that some LP cards will support SLI or Crossfire, but would this actually provide much of a boost over a single card? I don't expect to be able to play the latest games with everything maxed out. But if I could CrossfireX some LP cards and get maybe a 50% boost I'd probably consider it. I'm not a fanboy so I don't have a preference between ATI or Nvidia. Just want the best gaming I could get with a low profile setup.
 

Termie

Diamond Member
Aug 17, 2005
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While there are nice low profile cards, they aren't that compelling for crossfiring:

(1) This 6750 is way too expensive: http://www.newegg.com/Product/Product.aspx?Item=N82E16814131448

(2) There are a few LP 6670s, too, like this one: http://www.newegg.com/Product/Product.aspx?Item=N82E16814102958

The problem with those low profile cards, however, is that they don't have crossfire connectors. These cards would therefore need to run crossfire over the PCIe bus, which would limit their effectiveness.

Honestly, if you don't already have your case, I'd seriously consider one of the cube-shaped HTPC cases that allow the use of a full-size card. It will be much more effective, and unless you have a specific width constraint for placement of the case, they'll fit just as well into a small space.

If you must go low profile and want to game, your best bet is to try out one 6750 and see if it suits your needs. It's actually fairly competent as a low/mid-range gaming card.
 
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fuzzymath10

Senior member
Feb 17, 2010
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You probably don't want to run two of those cards in a low profile case. Odds are that they are going to get extremely hot and noisy, or the PSU won't be up to it.

I bought the Powercolor 5750 (the same as (1) above) over a year ago. The stock cooler is pretty noisy so I experimented until I ended up using a bent-to-low-profile Arctic Cooling Accelero which, of course, produces no noise.

Two 6670s might work, or two 7750s if they ever arrive in low profile.

Your options will be much cheaper and more plentiful if you get a case that supports full height and regular PSUs which I assume a slim case would not. Unfortunately, they are fatter cases.
 

QueBert

Lifer
Jan 6, 2002
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While there are nice low profile cards, they aren't that compelling for crossfiring:

(1) This 6750 is way too expensive: http://www.newegg.com/Product/Product.aspx?Item=N82E16814131448

(2) There are a few LP 6670s, too, like this one: http://www.newegg.com/Product/Product.aspx?Item=N82E16814102958

The problem with those low profile cards, however, is that they don't have crossfire connectors. These cards would therefore need to run crossfire over the PCIe bus, which would limit their effectiveness.

Honestly, if you don't already have your case, I'd seriously consider one of the cube-shaped HTPC cases that allow the use of a full-size card. It will be much more effective, and unless you have a specific width constraint for placement of the case, they'll fit just as well into a small space.

If you must go low profile and want to game, your best bet is to try out one 6750 and see if it suits your needs. It's actually fairly competent as a low/mid-range gaming card.


I'll look up how much of a hit running them without the crossfire connector I'd get. The price is too high but if I squeeze out enough FPS to make the difference between playing games on low, and playing them on medium I'd be willing to drop come cash. I'm probably stupid enough to go CrossfireX over PCI if it'd work and give me a semi decent boost.






You probably don't want to run two of those cards in a low profile case. Odds are that they are going to get extremely hot and noisy, or the PSU won't be up to it.

I bought the Powercolor 5750 (the same as (1) above) over a year ago. The stock cooler is pretty noisy so I experimented until I ended up using a bent-to-low-profile Arctic Cooling Accelero which, of course, produces no noise.

Two 6670s might work, or two 7750s if they ever arrive in low profile.

Your options will be much cheaper and more plentiful if you get a case that supports full height and regular PSUs which I assume a slim case would not. Unfortunately, they are fatter cases.

This case (Monuel 312s) supports regular ATX PSU's, not sure how it does as it looks really short. The space in the cabinet it'll be in isn't high enough anything much bigger. Sucks for me but I'm absolutely in love with how this case looks. So I guess I'll either have to go with a case I don't like as much that will accommodate a full size card, or bite the bullet and find the best low profile card I can get
 
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fuzzymath10

Senior member
Feb 17, 2010
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Just had a look. Those are really pretty cases :)

Given that it looks very living-room oriented, you probably do not want to get the 5750/6750 since it is very finicky in terms of cooler noise and durability over time (since you probably don't want to open up the case very often). As an HTPC case I always prefer low noise and low maintenance (i.e. passive cooling except case fans) but with a slim case things always become more complicated.

If you are curious, here is what I did: http://www.silentpcreview.com/forums/viewtopic.php?f=19&t=62194
 

Binky

Diamond Member
Oct 9, 1999
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That case is 4 inches tall. I'd be very very surprised if you didn't have heat issues in that case, which will also be shoved into a small cabinet.

I also have an HTPC that I shoved into a small case, which is then shoved into a small cabinet space. It's a tiny little Sempron 140 CPU using onboard video (until recently). With 3x80mm fans, this system generally idles well above 40c and easily hits 55c just watching a video. This is without a dedicated GPU and using a single core CPU at 2.7ghz.

So, good luck to ya. I'd seriously look into ventilation options for the cabinet. You can find some interesting AC powered cabinet fan setups on ebay using automatic thermostats.


LOVE the heatsink. That's hilarious.
 
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Termie

Diamond Member
Aug 17, 2005
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Just had a look. Those are really pretty cases :)

Given that it looks very living-room oriented, you probably do not want to get the 5750/6750 since it is very finicky in terms of cooler noise and durability over time (since you probably don't want to open up the case very often). As an HTPC case I always prefer low noise and low maintenance (i.e. passive cooling except case fans) but with a slim case things always become more complicated.

If you are curious, here is what I did: http://www.silentpcreview.com/forums/viewtopic.php?f=19&t=62194

Agreed - that's a nice case: http://www.newegg.com/Product/Product.aspx?Item=N82E16811280014

Assuming you're going for an AV-quality setup, just get the lower power 6670. You don't want the noise in that thing, and it's one less power cable to worry about (you're getting a modular PSU, right?!?).

Also, given your setup, I'd go with this HIS HD6670 instead of the Sapphire model I linked earlier: http://www.newegg.com/Product/Product.aspx?Item=N82E16814161397

It's shorter, so it will be easier to fit in the case, but it also has dual fans, which you'll need due to little airflow around the card, and could actually be quieter due to their open design. An added benefit is that it comes out a bit cheaper after rebate.

I'd still just get one to try it out, and then if you feel like being a guinea pig, buy two and let us know how it goes.

This review of 6570 crossfire will give you a general impression of the gains to be had (6670 will be a bit faster): http://www.tomshardware.com/reviews/radeon-hd-6570-radeon-hd-6670-turks,2925-13.html. Scaling is actually quite good - the data being passed through the bus isn't enough to saturate it with this level of card.
 
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QueBert

Lifer
Jan 6, 2002
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Agreed - that's a nice case: http://www.newegg.com/Product/Product.aspx?Item=N82E16811280014

Assuming you're going for an AV-quality setup, just get the lower power 6670. You don't want the noise in that thing, and it's one less power cable to worry about (you're getting a modular PSU, right?!?).

Also, given your setup, I'd go with this HIS HD6670 instead of the Sapphire model I linked earlier: http://www.newegg.com/Product/Product.aspx?Item=N82E16814161397

It's shorter, so it will be easier to fit in the case, but it also has dual fans, which you'll need due to little airflow around the card, and could actually be quieter due to their open design. An added benefit is that it comes out a bit cheaper after rebate.

I'd still just get one to try it out, and then if you feel like being a guinea pig, buy two and let us know how it goes.

This review of 6570 crossfire will give you a general impression of the gains to be had (6670 will be a bit faster): http://www.tomshardware.com/reviews/radeon-hd-6570-radeon-hd-6670-turks,2925-13.html. Scaling is actually quite good - the data being passed through the bus isn't enough to saturate it with this level of card.

I might just be a guinea pig. If the review was accurate a guy on there said his WEI is 7.1 with this card. I have a 4850, I know it's pretty old but I figured it would be faster. I get 6.9 on WEI. I play most games just fine so 7.1 with 1 card would be sweet. Maybe I'll be a real moron and buy 3 so I can try a super ghetto ghetto CrossfireX :D
 

Termie

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I might just be a guinea pig. If the review was accurate a guy on there said his WEI is 7.1 with this card. I have a 4850, I know it's pretty old but I figured it would be faster. I get 6.9 on WEI. I play most games just fine so 7.1 with 1 card would be sweet. Maybe I'll be a real moron and buy 3 so I can try a super ghetto ghetto CrossfireX :D

Don't go by the WEI score. The 6670 is definitely slower than the 4850 (except where the latter is VRAM limited); I'd say it's about a 10-20% deficit. In reality, the 4850 is much more like a 5750/6750 in performance.

You can compare the 6670 to the 4850 indirectly by looking at these two reviews:

- 4850 versus 5750: http://www.anandtech.com/show/2856/5

- 6670 versus 5750: http://www.anandtech.com/show/4278/amds-radeon-hd-6670-radeon-hd-6570/4

When crossfired, however, the 6670 will likely perform well above the 5770. Tom's compared 6570 crossfire to the 6790, for instance. I'd bet that 6670 crossfire would just about equal a 6850. Very good indeed.
 
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QueBert

Lifer
Jan 6, 2002
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I have a crazy idea which just might work here. Get a PCI-E riser card, run it + a PCI-E power cable out of the back of the case. And have a nice upper mid range video card in some sort of smaller than a case external enclosure.

Outside of this not being very practical, I don't really see why this wouldn't work. And I could tuck it all behind the case so it won't be visible. Is there any reason this wouldn't work?
 
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Termie

Diamond Member
Aug 17, 2005
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I have a crazy idea which just might work here. Get a PCI-E riser card, run it + a PCI-E power cable out of the back of the case. And have a nice upper mid range video card in some sort of smaller than a case external enclosure.

Outside of this not being very practical, I don't really see why this wouldn't work. And I could tuck it all behind the case so it won't be visible. Is there any reason this wouldn't work?

I'm pretty sure you won't find a PCIe riser card long or flexible enough to actually be positioned outside of the case.

Images: https://www.google.com/search?q=PCI...ct=mode&cd=2&ved=0CFcQ_AUoAQ&biw=1229&bih=794

Maybe, just maybe, you could get one of the PCIe x4 cable to work, and the bandwidth hit wouldn't be that bad with a low/mid-range card. But honestly, anything much more powerful than a 6750 would start to lose performance over an x4 connection.

That, and this would be a butt ugly way to finish off a high-end HTPC case. :)