amd 7870xt and 7850 crossfire

[jackwal]

ok so i just put a 7850 in my rig thinking my 7870xt would clock it self down and run ok in stead it just crashes when i get to the windows load up screen is there any reason why this is happening 

[Darel321]

try to manualy set the clock... downclock the 7870 or oc the 7850

[Hodor]

7870xt cannot be crossfired with 7850. Found that out after 30s of google research.

[EunSoo]

5 minutes ago, jackwal said:

ok so i just put a 7850 in my rig thinking my 7870xt would clock it self down and run ok in stead it just crashes when i get to the windows load up screen is there any reason why this is happening 

For Crossfire, the two cards have to be the same model. You would need 2 7850s or 2 7870xt

[TheRandomness]

2 minutes ago, SCGazelle said:

For Crossfire, the two cards have to be the same model. You would need 2 7850s or 2 7870xt

Well, they're the same chip sooo...

Forgot the 7870xt was a cut down 7950/7970.

[Mr.Meerkat]

4 minutes ago, SCGazelle said:

For Crossfire, the two cards have to be the same model. You would need 2 7850s or 2 7870xt

not true but they have to have the same core, the 7870xt is a cut down 7950/7970 so it can be crossfired with the 7950 and 7970 but not the 7850 as it's a completely different core  

[Sakkura]

4 minutes ago, SCGazelle said:

For Crossfire, the two cards have to be the same model. You would need 2 7850s or 2 7870xt

No. They just have to be the same chip. A "real" 7870 would work just fine with a 7850. The 7870 XT should have been called the 7930, because it's the same chip as the 7950 and 7970.

[Darel321]

ohh.... its 7870 xt.. well that wont work with 7850... you need a normal 7870 to work

[afyeung]

6 minutes ago, SCGazelle said:

For Crossfire, the two cards have to be the same model. You would need 2 7850s or 2 7870xt

No, they just have to use the same base chip. For example, 290 and 390x, 390 and 290x, 290 and 290x

[EunSoo]

1 minute ago, Mr.Meerkat said:

not true but they have to have the same core, the 7870xt is a cut down 7950/7970 so it can be crossfired with the 7850 and 7870 but not the 7850 as it's a completely different core  

Ok, I don't really know the AMD HD series.