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7990 Running hot - Very hot! (100c+)


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7990 Running hot - Very hot! (100c+)
« on: December 07, 2013, 10:44:32 pm »
Hi everyone

I bought 4! 7990 for gaming and litecoin mining. But it is just silly how warm it gets. I tried to change the voltage and power usuage. But it seems like the cards are voltage locked ???

Is there any workaround for this or new software needed to flash the card with?

Many thanks


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Re: 7990 Running hot - Very hot! (100c+)
« Reply #1 on: December 09, 2013, 04:59:49 am »
This should help, custom bios, also details regarding under volting the 7990 to reduce temps.  8)

Please read full details here >>

Quote from: LtMatt, 19th Nov 2013 - OcUK Forums
Using the stock 7990 bios the card will throttle under moderate load forcing the card into its non boost state of 1.170v 950/1500. In order to get optimum performance and smoothness from the 7990 i highly recommend flashing this custom bios to remove the throttling issues. Using this bios will allow the card to operate at its boost state of 1000/1500 @1.200v 100% of the time.

If you plan to run the card at stock clocks of 1000/1500 I highly recommend experimenting lowering the default voltage using MSI Afterburner to 1.125v-1.175v. Doing so will reduce temperatures significantly. This will vary based on the Asic of your card and how much voltage it needs to be stable at a given clock.

Bios Features V3

Better performance over the stock bios
GPU usage will not fluctuate so much as the card does not switch between power states
50% power tune for extended overclocking
250W TDP at 0% power tune (default is 179W with 20% power tune)
*300W TDP at 20% power tune.

*The 7990 has built in protection to stop the card from drawing too much power. It should turn off to protect itself if you add too much voltage or let temps get out of control. However i urge you to be responsible and not go overboard with the voltage. Be sensible with your overclocks and voltage settings. For air cooling i recommend voltage no higher than 1.250v. For water cooling you should be ok up to 1.350v.

I accept no responsibility for damaged cards. Flash at your own discretion.

Bios Flashing Instructions

You might want to write parts of this down or print it out.

Included in step 7 is the download link to the two custom bios which you will flash. They are labeled Malta1 (master bios for gpu1) and Malta2 (slave bios for gpu2). Its very important you flash the master bios to gpu 1. If you flash the mater bios to the slave or the other way around the card will not function correctly. If you follow the guide closely you cannot go wrong. :)

First of all you need to create a bootable usb stick to flash the cards in DOS.

1. Download and install the USB disk format tool here.

2. Download the Windows98 system files here.

3. Create a folder called Win98boot on your desktop, extract the files from step 2 into the folder.

4. Plug in your usb stick. Launch the USB disk format tool. Copy these settings, then click format. You need to select quick format, tick dos startup and select the Win98 folder, like ive done below.

5. Click start, then ok and it should do it.

6. Download atiflash. Extract it onto the usb stick.

7. Download my 7990 bios. Extract it and cut and paste it into the usb stick.

8. If you've done everything correctly your usb stick folder contents should look like this. Do not worry if you have more or less files than what appears in the screenshot. You may have more files than in the screenshot, depending on what OS you use.

9. Make sure the 7990 in your pc is switched onto bios 1.

10. Uninstall gpu drivers and any overclocking apps. Do not keep settings delete everything.

11. Restart your pc. Before you hear the beep keep tapping F8. Boot from the usb stick.

12. You should be at dos prompt. Type atiflash -i to get the adapter number for both your gpu's. Typically it will be 0 and 1, unless you have a gpu in a third pci-e slot. You need the adapter number to tell it which gpu to flash.

13. To flash gpu 1 (master 7990) type atiflash -p -f 0 Malta1.rom and hit enter.

Wait for it to finish. It will prompt you to restart but before we do that we need to flash the second gpu as well.

Now do the second gpu (slave 7990)

Type atiflash -p -f 1 Malta2.rom

Once that has completed and you get a notification saying you can restart press Ctrl+Alt+Delete to restart your pc.

All going well you should get a display and boot back into windows. Now you can reinstall fresh new drivers etc. Boost voltage and boost clock is disabled, your card thinks its a non boost card from now on in and you have the option to select 50% power setting as standard with every driver install.

If something goes wrong and you get no display from the cards after flashing the bios. Turn the pc off and flick both cards bios switch to position 2 to use the stock backup bios. Turn the pc back on and all will be ok.

Good luck. :cool:

Thanks to Kaboom from who helped me learn and create my own bios. His thread where all this started can be found below. For anyone looking to get a bios made for them for other cards, this is the man to go to. :)
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