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Crossfiring two different ATI cards

Noughtboy

Noughtboy

Noughtboy

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Essex
Having to retype this entire series of questions from scratch because of a timeout when trying to preview the post has left me a remarkably bitter and twisted individual.

I am posting under the GPU section because that is my primary question and the other's follow on from this.

I currently have a legacy AMD64 S939 3200XP Venice CPU in an Asus A8R-MVP MB. I am using a 3DConnect ATi Radeon X1900XT 256MB dual DVI card. I am looking to upgrade to a 3 screen trading platform which will not be used for games but purely for email/browsing/trading.

Having looked at the price of Display Port monitors, it is cheaper to use two GPU’s each with two ports than buy one Eyefinity capable card and at least one DP monitor.

I am looking to power this trading platform with an AMD Athlon II X4 635 inserted into a Gigabyte GA-MA785GT-UD3H AMD 785G http://www.overclockers.co.uk/showproduct.php?prodid=MB-210-GI&groupid=701&catid=5&subcat=1481 or similar. Feel free to correct me on this. My two options to run three screens in this setup seem to be:

1. Use my X1900XT card and a Powercolor X800 GTO16 256MB card in crossfire. Is this actually possible to crossfire two different cards and would I need any additional cables/software etc to set it up?
Or
2. Use one of the above cards along with the MB’s onboard Radeon 4200 GPU. I assume CF is not a possibility here and really just need to have a large real estate for viewing all my stuff.

I suppose option three is CF the two cards in option one in my current Asus A8R-MVP MB using my current 3200XP chip.

Lastly, would this Be-Quiet 530w Pure Power PSU power the 2 GPU’s http://www.be-quiet.net/be-quiet.net/index.php?StoryID=522&websiteLang=en? It has two 12v power rails putting out 22A each but I am not certain if I will need four power rails to drive two cards. I am getting conflicting reports from eXtreme powersupply calculator telling me I'll need 467w including all additional hardware and capacitor aging etc to Asus telling me I will need a 700w PSU . Bearing in mind I will not be OC'ing this system and may even underclock the GPU's a little.

I hope my questions are lucidly presented and easy to answer. Thanking you in advance for your response.

NB
 
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Firstly, you don't need Crossfire at all with what you're planning. Crossfiring is using 2 (or more) GPUs to power the same output and with any Crossfire setup you are limited to only the outputs on one card, the other card's outputs will not work. This means to use 3 screens and Crossfire, you are looking at the latest 5xxx series cards and Eyefinity.

The good news is, as you're not planning on gaming, you don't need the extra grunt Crossfire provides, so you can turn Crossfire off. This causes the second card's outputs to become live and usable with each card powering only the screens that particular card is attached to.

You should be able to plug one of your GPUs into that motherboard and have 1 screen working off the motherboard's output, and two off the GPU's output. However, I've never tested this so cannot confirm it works. The other option would be to plug both GPUs into a Crossfire board (any will do), turn off Crossfire and then plug up to 2 screens into each GPU - do you fancy running 4 screens? For gaming, you will only have the power of one card - whichever one that screen is attached to - but for non-gaming this will work perfectly.

Good luck, and don't forget some pictures when you've got it up and running. :)

P.S. Forgot to say - welcome to the forum! :)
 
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Thanks for the quick reply Stu. OK, so I do not need to CF the cards. Does anyone else have any further insights as to whether the two outputs from the GPU and one off the MB GPU would work? Has anyone actually done this?

Lastly, as per the last paragraph, if I have to use both the X1900XT and X800 GTO16 GPU's, will the Be-Quiet 530 PSU have enough juice?

NB
 
i was messing around with laptops and docking stations, i couldnt get 2 outputs from 2 VGA signals, so im guessing that the channel has been used and you cant simply create a new one, so you might run into that issue.

You can however run a DVI and VGA together, but 2 VGA's i reckon is a no go
 
Noughtboy said:
2. Use one of the above cards along with the MB’s onboard Radeon 4200 GPU. I assume CF is not a possibility here and really just need to have a large real estate for viewing all my stuff.
Click to expand...

hybrid crossfire (as this would be) is very restricted to what mix of cards it will tolerate. Only the 2400 and 3400 series cards work with onboard gfx in hybrid mode If I recall.
 
Since you're not gaming, you don't need crossfire. You can use the motherboard's vga as well with a card, effectively giving you three displays, although you do have to enable it in the BIOS. The motherboard and cpu you have chosen will do nicely, and you can keep your current X1900XT as it will be enough to browse the net.
 
Invaliduser said:
hybrid crossfire (as this would be) is very restricted to what mix of cards it will tolerate. Only the 2400 and 3400 series cards work with onboard gfx in hybrid mode If I recall.
Click to expand...

that isnt hybrid crossfire. hybrid crossfire does exactly what crossfire does, but instead does it with the onboard gfx and an add-in gpu. It is however poorly supported as you mentioned, not that its much of an advantage crossfiring onboard gpu's.

Noughtboy, you can use either the two cards, the onbard gpu and one card, or all 3 if you really want to be pimp :p

the onboard graphics will give you a 3rd display - exactly what you want.

i found this from a good few years ago:

ati_surround.jpg



finally, the psu will be more than adequate :)
 
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Thanks to everyone for the comments. Sorry for the delay in coming back but with setting up the box and the holidays etc things were higgildy piggildy. I have got the system working with my GTO16 256MB running two monitors at 1920*1080 in DVI and the third running of the Radeon HD 4200 on VGA also at 1920*1080 (as DVI seem not seem to work).

I had to install an older version of Catalyst (9.2 I think) and after a little struggle it all seems to work so long as I run the VGA output at 16 bit as 32 bit colour seems to cause a lot of tearing of the image whenever something was moved on the screen.

Thanks for all the help. Just as an aside, I already had the two cards mentioned above and did not want to buy two cheap cards if I could have used what I had.

I can't seem to insert a screenshot as requested but take my word it is working.

Regards

NB
 
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