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Michal_Kierzynka
Journeyman III

AMD stream doesn't detect 2 x 4870

Hi to all,

I have two radeon 4870. I have CrossfireX turned off. Driver version: 9.4, OS: Windows XP 32bit. When I run "FindNumDevises" program delivered with CAL the output is:

Supported CAL Runtime Version: 1.3.185
Found CAL Runtime Version: 1.4.255
Use -? for help
CAL initialized.
Finding out number of devices :-
Device Count = 1
CAL shutdown successful.

 

Why does this program detect only one device? Any advices?

 

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12 Replies
ryta1203
Journeyman III

AMD stream doesn't detect 2 x 4870

Read the FAQ.

EDIT: I thought I saw in a FAQ (that I can't find now of course ) that you have to turn Crossfire ON, which I oddly thought contradicted AMDs early statements that Crossfire needed to be off, but hey, what do I know.

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Michal_Kierzynka
Journeyman III

AMD stream doesn't detect 2 x 4870

You're absolutely right. Thanks. The CrossFireX must be enabled. But to be honest, I found it a bit confusing, because in NV CUDA the SLI must be actually disabled.

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emuller
Journeyman III

AMD stream doesn't detect 2 x 4870

In Linux, crossfire should not be enabled, and I imagine this is true for Windows as well.

There are clear instructions for both Windows and Linux in <atical>/CAL_Documentation/CAL_FAQ.pdf at least since the 1.4beta release.

 

 

 

 

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Michal_Kierzynka
Journeyman III

AMD stream doesn't detect 2 x 4870

I read the /CAL_Release_Notes.pdf and /CAL_Documentation/CAL_FAQ.pdf.

Then I just wanted to edit my previous post (to correct it), but emuller was faster

 

To sum up:

1) To have both card recognized by Stream, CrossFire doesn't have to be enabled, if you tell your OS to enable display on the second GPU (Windows -> "Extend my Windows desktop onto this monitor").

2) If CrossFire is enabled in WindowsXP, the amount of local memory is reduced by half.

3) Under Linux and Vista Stream uses only one GPU if CrossFire is enabled -> one should disable CrossFire.

 

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wgbljl
Journeyman III

AMD stream doesn't detect 2 x 4870



1) To have both card recognized by Stream, CrossFire doesn't have to be enabled, if you tell your OS to enable display on the second GPU (Windows -> "Extend my Windows desktop onto this monitor").

How to make both cards recongnized by Stream in Linux?

Thanks for any help

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Michal_Kierzynka
Journeyman III

AMD stream doesn't detect 2 x 4870

Originally posted by: wgbljl


 

1) To have both card recognized by Stream, CrossFire doesn't have to be enabled, if you tell your OS to enable display on the second GPU (Windows -> "Extend my Windows desktop onto this monitor").

 

 

How to make both cards recongnized by Stream in Linux?

 

Thanks for any help

 

 

The answer is in "/atical/CAL_Documentation/CAL_FAQ.pdf" file.

 

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riza_guntur
Journeyman III

AMD stream doesn't detect 2 x 4870

Originally posted by: Michal.Kierzynka I read the /CAL_Release_Notes.pdf and /CAL_Documentation/CAL_FAQ.pdf.

 

Then I just wanted to edit my previous post (to correct it), but emuller was faster

 

 

 

To sum up:

 

1) To have both card recognized by Stream, CrossFire doesn't have to be enabled, if you tell your OS to enable display on the second GPU (Windows -> "Extend my Windows desktop onto this monitor").

 

2) If CrossFire is enabled in WindowsXP, the amount of local memory is reduced by half.

 

3) Under Linux and Vista Stream uses only one GPU if CrossFire is enabled -> one should disable CrossFire.

 

 

 

How do I extend windows desktop if I currently only have one monitor attached? I have deactivated crossfirex. The extend checkbox haven't checked after the confirmation.

So far I found the gpu memory is really small, thus by consider I have 2 4850 512MB I would like to sum up the memory of both cards in XP 32.

In samples with crossfirex on, I try to use the second gpu to calculate matrix multiplication and the result seems better by tens GFLOPS. When the dimension of matrix goes beyond 5000, the program crashed. I think it because the memory is not enough.

Does anyone have a clue?

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Michal_Kierzynka
Journeyman III

AMD stream doesn't detect 2 x 4870

 

How do I extend windows desktop if I currently only have one monitor attached? I have deactivated crossfirex. The extend checkbox haven't checked after the confirmation.

I have the same problem. Maybe some KVM switch would help. I'll have to give it a try.

 

So far I found the gpu memory is really small, thus by consider I have 2 4850 512MB I would like to sum up the memory of both cards in XP 32.

 

In samples with crossfirex on, I try to use the second gpu to calculate matrix multiplication and the result seems better by tens GFLOPS. When the dimension of matrix goes beyond 5000, the program crashed. I think it because the memory is not enough.

 

Does anyone have a clue?

 

I don't understand your problem exactly. If you want to have 2x 512MB (1GB), crossfire have to be disabled.

 

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riza_guntur
Journeyman III

AMD stream doesn't detect 2 x 4870

Originally posted by: Michal.Kierzynka


 

 

 

How do I extend windows desktop if I currently only have one monitor attached? I have deactivated crossfirex. The extend checkbox haven't checked after the confirmation.

 

 

I have the same problem. Maybe some KVM switch would help. I'll have to give it a try.

 

 

 

 

So far I found the gpu memory is really small, thus by consider I have 2 4850 512MB I would like to sum up the memory of both cards in XP 32.

 

 

 

In samples with crossfirex on, I try to use the second gpu to calculate matrix multiplication and the result seems better by tens GFLOPS. When the dimension of matrix goes beyond 5000, the program crashed. I think it because the memory is not enough.

 

 

 

Does anyone have a clue?

 

 

 

 

I don't understand your problem exactly. If you want to have 2x 512MB (1GB), crossfire have to be disabled.

 

 

 

I mean: Do I still get 1GB and computing power of 2x4850 after disabling CF but the extend desktop still haven't been checked after I tried to check it?

Do you get it? sorry for my bad English

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