4870x2 CrossfireX compatibility with Asus Rampage Extreme?

[shiver76]

As the title. though all ok when i play with one 4870x2( anyone of two cards), but when i set both two 4870x2 cards to make CrossfireX, the system can't post at all.
there's no vga signal output. but the debug led of mainboard shows system boot ok

till now i have tried :
1:adjust the jumper of the back of 4870x2
2:change another one crossfire bridge cable

but doesn't help.

i have tested both two pci-e slot with single 4870x2 card, works fine. but still no post when crossfireX. OMG.....



my components:

cpu: qx9650 boxed
mb: asus rampage extreme x48
vga: powercolor hd4870x2 x 2
power: tt toughpower 1500w
ram: G.Skill F3-12800CL7D-4GBPI(2gx2)

it that a compatibility issue? what should i do now ?

 

[boogah]

put 2 cards in without the crossfire bridge. Let windows install both cards shut down put in the bridge then boot up the computer.

 

[Jmatt110]

Try booting at stocks clocks for everything and make sure your mobo BIOS is the most up to date one.

 

[shiver76]

put 2 cards in without the crossfire bridge. Let windows install both cards shut down put in the bridge then boot up the computer.

system won't post either with crossfire bridge installed or not........
there's no vga signal after i plug the pci-e 6pin&8pin on second card.

 

[erocker]

Sorry for the n00bish question, but do you have the DVI cable in the correct socket?

 

[boogah]

which card did you plug the monitor cable in ?

 

[shiver76]

Sorry for the n00bish question, but do you have the DVI cable in the correct socket?

i have tried all four sockets of two 4870x2 cards. but no post.
normally, i plug the dvi cable in top socket of master card(this card nearby cpu)

 

[boogah]

Some time i have to double boot the system to get video to post when doing crossfire with my P5E X48 (pretty much same board) it would boot up with the fans n stuff running but no video so i hold the power button down until it shuts off then turn it back on and it would boot normally.

 

[erocker]

Some time i have to double boot the system to get video to post when doing crossfire with my P5E X48 (pretty much same board) it would boot up with the fans n stuff running but no video so i hold the power button down until it shuts off then turn it back on and it would boot normally.

Indeed this works!

 

[Fitseries3]

you need to bump your SB voltage up to handle the cards. NB needs a small bump too.

 

[boogah]

hey wait y did erocker get a thank for quoting me > p hahaha

 

[zithe]

Because erocker defines awesome around here.

edit: crap noticed the dates. I do that a lot..

 

[Fastmix]

Do you have any option on the bios menu to select 1 videocard, 2 videocard, or crossfire.

I am saying this..because my system does.