Trouble Overclocking 5850 to 900MHz shader - page 2.

fpgaminer

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Quote

my overdrive file:

Thank you for that.

So I checked, and at 900MHz the chip receives 1.088V, the same as yours. Undecided

I was able to run the card at 850MHz all through last night. So it's just 900 MHz specifically that's giving me unhappy times. Maybe I should try 899 ...

Quote

I am under the assumption that this is what happens when you hit the BIOS limit. I could be wrong.

Perhaps. The odd thing is that, under Windows, it can run 900MHz for a while. About an hour. And then it goes KERBLEWIE. If it were a hard limit in the BIOS I assume it would just go KERBLEWIE immediately.

Also, in Windows it resets the driver when things go awry, instead of locking up like Ubuntu does. From there, it's back to normal (at 900MHz), except the miner (phoenix) has stopped because of the driver reset.

rezin777

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Quote from: fpgaminer on April 28, 2011, 12:39:19 AM

The issue is that going to 900 makes the card go KERBLEWIE.

I am under the assumption that this is what happens when you hit the BIOS limit. I could be wrong.

grndzero

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Quote from: fpgaminer on April 28, 2011, 12:39:19 AM

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The BIOS has clock speed limits.

I know. This board lets me go up to 900 without any mods, in all the overclock tools I've tried. So that isn't the issue. The issue is that going to 900 makes the card go KERBLEWIE.

Quote

The 5870 bios ups the voltage allowing it to run at higher clock speeds.

Thank you for clarifying what you meant. I remember that AMDOverdriveCtrl let me adjust the voltages. If that's true, would that be the same as BIOS flashing? And what kind of voltage is appropriate for 900MHz?

I'm a bit wary of BIOS flashing the card, since I don't have a spare PCI card to help fix it if things go awry (only one PCI-E slot on that machine Sad

)

Thank you for the suggestions and help so far!

Understandable. I have 4-5 crappy PCI cards laying around, so I didn't have a problem trying out all the tweaked BIOS that were posted. I think I've had to recover 3 times now. lol

I didn't try AMDOverdriveCtl until I had already flashed the BIOS. Upping the voltage with AMDOverdriveCtl could work, but you may run into a hard limit with the BIOS.

If aticonfig --odgc says that the BIOS supports up to 900 then try AMDOverdriveCtl .. my overdrive file:

Code:

If the BIOS doesn't say 900 then try changing the 90000 to your current running speed, etc 87500 with the 1088 voltage and reassess with aticonfig --odgc and see if it raises the limit to 900. If so then try to step it up with either aticonfig or overdrivectl.

If that doesn't work then you're probably hitting a hard BIOS limit.

fpgaminer

hero member

Activity: 560

Merit: 517

Quote

The BIOS has clock speed limits.

I know. This board lets me go up to 900 without any mods, in all the overclock tools I've tried. So that isn't the issue. The issue is that going to 900 makes the card go KERBLEWIE.

Quote

The 5870 bios ups the voltage allowing it to run at higher clock speeds.

Thank you for clarifying what you meant. I remember that AMDOverdriveCtrl let me adjust the voltages. If that's true, would that be the same as BIOS flashing? And what kind of voltage is appropriate for 900MHz?

I'm a bit wary of BIOS flashing the card, since I don't have a spare PCI card to help fix it if things go awry (only one PCI-E slot on that machine Sad

)

Thank you for the suggestions and help so far!

grndzero

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Activity: 392

Merit: 250

Quote from: fpgaminer on April 27, 2011, 08:27:25 PM

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The highest I could get my 5850's to before freezing was 875. I got them up to 900 by flashing them with 5870 BIOS.

Just to be clear, you had to flash your BIOS to make it stable, or to even set it to 900?

I can set my card to 900 MHz no problem. It's just that the display freezes and I have to do a restart (REISUB).

What does that BIOS do that would prevent the card from failing at higher clock speeds?

Just to be able to get to 900 core speed. Mine wouldn't go past 875.

The 5870 bios ups the voltage allowing it to run at higher clock speeds.

On the Reference boards most of the PCB's are the same, the 5850 just has less stream processors.

rezin777

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Quote from: fpgaminer on April 27, 2011, 08:27:25 PM

Just to be clear, you had to flash your BIOS to make it stable, or to even set it to 900?

I can set my card to 900 MHz no problem. It's just that the display freezes and I have to do a restart (REISUB).

What does that BIOS do that would prevent the card from failing at higher clock speeds?

The BIOS has clock speed limits.

fpgaminer

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Activity: 560

Merit: 517

Quote

The highest I could get my 5850's to before freezing was 875. I got them up to 900 by flashing them with 5870 BIOS.

Just to be clear, you had to flash your BIOS to make it stable, or to even set it to 900?

I can set my card to 900 MHz no problem. It's just that the display freezes and I have to do a restart (REISUB).

What does that BIOS do that would prevent the card from failing at higher clock speeds?

grndzero

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Activity: 392

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Quote from: fpgaminer on April 27, 2011, 08:10:23 PM

I recently bought a Sapphire HD 5850 ($150 after taxes) ... so I can race it against my FPGAs Tongue

I have Ubuntu 10.10 32-bit, fglrx 8.801, 2.1 SDK. Using aticonfig I can overclock up to 900MHz, which is good enough for me, except that at that speed it freezes within a few seconds (screen no longer responds; have to REISUB). It ran overnight at 765MHz just fine. In Windows it could run at 900MHz for about an hour, and then Windows restarts the driver because it stops responding.

Is my card just a weak batch and won't ever get to 900MHz stable, or is there something else I can do?

Thank you!

The highest I could get my 5850's to before freezing was 875. I got them up to 900 by flashing them with 5870 BIOS.
http://www.techpowerup.com/vgabios/61848/ATI.HD5870.1024.091112.html

rezin777

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This could be a possible BIOS limitation.

If it is a reference board, you can easily flash the BIOS to allow for higher overclocking limits. Simply pick a BIOS from a different reference board that allows for higher overclocking.

If it is a non-reference board, you should download RBE from http://www.techpowerup.com/downloads/1962/TechPowerUp_Radeon_Bios_Editor_v1.28.html and modify your BIOS to the limits you prefer.

fpgaminer

hero member

Activity: 560

Merit: 517

I recently bought a Sapphire HD 5850 ($150 after taxes) ... so I can race it against my FPGAs Tongue

I have Ubuntu 10.10 32-bit, fglrx 8.801, 2.1 SDK. Using aticonfig I can overclock up to 900MHz, which is good enough for me, except that at that speed it freezes within a few seconds (screen no longer responds; have to REISUB). It ran overnight at 765MHz just fine. In Windows it could run at 900MHz for about an hour, and then Windows restarts the driver because it stops responding.

Is my card just a weak batch and won't ever get to 900MHz stable, or is there something else I can do?

Thank you!

Topic: Trouble Overclocking 5850 to 900MHz shader - page 2. (Read 4248 times)