Will these two cards work in crossfire?

KreitzAIC12

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Jul 1, 2014
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I own this card....(SAPPHIRE 100354OC-2L Radeon HD 7870 GHz Edition 2GB 256-Bit)
http://www.newegg.com/Product/Product.aspx?Item=N82E16814202025

Will it work in crossfire with this card??...SAPPHIRE 100364-4GL Radeon R9 270X 4GB 384-Bit
http://www.newegg.com/Product/Product.aspx?Item=N82E16814202049

I've heard mixed things already about CF'ing the 7870 with R9 270's/270x's. Something about they have to have the same GPU core??? Will the 4gb/384 bit of the 270x be an issue working with my 2 gb 256 7870? Also the 270x 4gb has 2048 shaders, where my current 7870 has 1280.
 
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most games that support crossfire /no profile you can use a known working profile from another game in ccc, i play never winter and it has the same issue, i use the bf4 profile and xfire works great.

a 4gb 270x isnt worth it, 2 2gb cards will do just fine,
270x doesnt have 2048 shaders it has 1280 as well you will be fine since its the same card the specs you have are from a 280x/7970 which will not work with a 7870

i though they did make a 4gb 270x but is will still have the same shader count and memory bus. it looks like the specs on newegg arent correct.

I cant even find that card on sapphires site
 

KreitzAIC12

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Jul 1, 2014
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Is there any benefit to using 2x 2gb cards vs a single 4 gb card? I'm wondering because if 2 Gb of vram cant be used when in crossfire 4gb+2 gb - 2gb = 4 total. In crossfire the two cards technically running twice the memory bus? So 512 bit? Same with shaders, do I get 2560 using the two cards?
Reason I ask all this is because, say there's a game that doesn't support multi GPU's, I could turn off the lesser card and use the single 270x and it should maintain it's 4gb holding. Then I play a different game that DOES support crossfire, then I would turn the lesser card back on, I would have 4gb total still, but twice the mem bus and shaders? That last part about the mem bus and shaders is what I mostly don't know too much about.

 
most games that support crossfire /no profile you can use a known working profile from another game in ccc, i play never winter and it has the same issue, i use the bf4 profile and xfire works great.

a 4gb 270x isnt worth it, 2 2gb cards will do just fine,
 
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