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lol, why would 8x 8x would be better? then 16x 4x? I thought it only gives out 4x output to the 16x, then giving 8x to the 8x main gpu. maybe u shuld see how ur bios reacts to xfire, it usually would say, if u put 2x video card, one slot will work 16x 8x or 8x 8x, or 16x 4x. etc..
 

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there is really no diff between x8 and x16 except in cases like the 4870x2 or the GTX295. x8 + x8 will be much better. x4 will bottleneck the card a LOT.

u can look it up if u want, but there isnt a big diff between x8 and x16 when it come to most graphics cards, but x4 vs x16 or x4 vs x8, x4 will bottleneck a lot
 

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oh really? Let me know how u can change the speed of the pci-e to 8x/8x with the mobo asus m3a78-t, I just checked on the bios, and couldn't seem to find a way to do it..
 

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make sure ur bios is updated and ur drivers are updated.

u should be able to do it in the catalyst control panel

i dont have a lot of experience with ATi or dual-card solutions, i have done research this tho...

not sure exactly where to change it at, but i know x8 + x8 is much better
 

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i believe you have your second card in the wrong pci-e x16 slot try the other as it says you can run either x16 + x4 or x8 + x8 and i believe its slot dependant

EDIT: found this at legit reviews

The Asus M3A78-T motherboard has 3 x16 PCI-E slots on it. The top PCI-E slot is fully 2.0 compliant, and runs at a full x16 mode. The black PCI-E slot is also fully 2.0 compliant, but runs at x4 speeds only, while the fully 2.0 compliant white slot runs at a maximum of x8 speeds.

so you need the blue + white slots

hope that helps

EDIT2: from newegg and legit reviews bundle description the geniuses at asus didnt include a crossfire bridge long enough BRILLIANT ASUS
 

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Thanks for that info, I have put the xtra card in the white slot, but xfire couldn't be enabled, that is the reason why i put it on the black slot. everytime i put it on the white slot, it cant catch the card. that is why i left it on the black slot, and the main slot. thanks for the help though..
 

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they work, you just need to install your drivers while they are in those slots. Uninstall your drivers and reinstall them while they are in the blue and white slots and it all works great. Just did it myself
 

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x4 gives you 1.6 GBps
x16 gives you 6.4GBps

X8 gives you 3.2GBps

So would x8 + x8 give you 6.4GBps,
and x16 + x4 give you 8GBps???
 

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but ur card in the x16 slot would have to wait on the info that the card in the x4 slot rendered, so ur wasting cycles with the x4 card. and few cards NEED the full x16 bandwidth, most dont come close to using it, but x4 will bottleneck you.
 

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Quote:


Originally Posted by Pao
View Post

they work, you just need to install your drivers while they are in those slots. Uninstall your drivers and reinstall them while they are in the blue and white slots and it all works great. Just did it myself


Last time i had it on the blue and white, it didnt work for me, i scrubbed out the drivers, i even downgraded the bios and the drivers, made sure i uninstall, and they didnt work, so i gave up, and was bout to return the other card. and then, i went and tried it one last time, and put it on the black slot, and viola` it worked... so i dont think im goin back to try and fiddle w/it when it already works, maybe one day when im really really really bored..
 

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lol, thats computers for u. cant tell u how many times i couldnt get a computer to boot, then i pressed the button "one last time" and it came on.

its like they know they pushed us to the limit... creepy...

what will happen if they take over!?!?! THEY KNOW WHAT WE ARE THINKING AND THEY ARE MESSING WITH US!!!!

lol jk man, grats on getting it running
 

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If you have pci-e 2.0, then you probably won't see a performance increase with 8x 8x over 16x 4x since (a) pci-e 2.0 4x runs at pci-e 1.1 8x equivalent, and (b) a second 4830 cf'd in an 8x equivalent pci-e 1.1 8x slot likely won't be bottlenecked all that much. But taking the first card into 8x from 16x might kill some performance (since CF doesn't scale linearly, the main card should get the highest bandwidth slot, with the second card in the slower slot).

If it were pci-e 1.1, then I would say do the 8x 8x. But since it's 2.0 (I think...), then you should keep the 16x 4x.
 

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Quote:

Originally Posted by hoth17 View Post
x4 gives you 1.6 GBps
x16 gives you 6.4GBps

X8 gives you 3.2GBps

So would x8 + x8 give you 6.4GBps,
and x16 + x4 give you 8GBps???
Just like cores in a quad core are separate units, so are graphic cards. You don't add up the bandwidth just like you don't add up the frequency of the cores.
 

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Quote:

Originally Posted by IntelConvert View Post
lol, thats computers for u. cant tell u how many times i couldnt get a computer to boot, then i pressed the button "one last time" and it came on.

its like they know they pushed us to the limit... creepy...

what will happen if they take over!?!?! THEY KNOW WHAT WE ARE THINKING AND THEY ARE MESSING WITH US!!!!

lol jk man, grats on getting it running

LoL, trust me, i was bout to kill someone!! I went thru 3 different mobo to try and get it fixed. Space was the issue for me, i wanted the cards to have enough space from each other.. but I guess i couldn't have that, the space mines have now are separated by a single piece of paper. My main one runs hot on underload, but only at around 53c. and it runs now under 40c on idle. SO im happy, n i havn't found ne conflicts with it..
 

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I saw a massive diffrence in performance when I went from 16x/4x to 16x/16x. This was with some X1950's though.
 
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