I installed my 4850X2 card last night, Crossfire enabled, Cat 9.5 and 0.19f. Running a cmdline of n1 w1.1

In GPU-Z, it states both GPUs are running at ~50%. Normally my bog standard 4850 either runs at 70% or 95% (depending on the WU).

So, is GPU-Z saying 50% for each GPU normal? My intuition says no based on individual 4850s, but I'll see the RAC after a couple of days use. I was wondering what peoples experiences were.

I've done the disable CF/enable 2nd GPU tweak - meant one GPU ran in 3D, the other in 2D, both hit 70% in GPU-Z. Then one GPU needed VPU recovery after a few minutes, so this isn't an option. I tried n2 n3 and n4 in cmdline, no improvement in that respect.

The output does state 2 CAL devices found, which is always a plus. But a 74 credit WU is taking 160seconds, about twice as long as it did on a single 4850. (So in 160 seconds, one 4850X2 does 2 WUs, but 2x 4850 does 4...)

You could argue that 2x50% = 100%, however I'm under the impression that the GPU-Z GPU load bar is just for that GPU, thus out of 100 for that individual GPU.

Thoughts please :)

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Should note I'm using BOINC 6.4.7, though I doubt that makes a difference in this case.

Machine is not running any other projects either.

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This is the Commands I use on a Dual 4850 X2 Setup with a Q6600 running @ Stock 2.4 GHZ Speed. the Box runs 12 Milkyway Wu's & 3 CPDN Wu's with these Commands on that Box anyway.

Don't know if they would work for you or not, the last to lines should work as they work on all my Box's running a ATU GPU Capable Card. The Top line is the one I play with, I have it set to anywheres from 1.0 to 0.01 & in between to get the Cards to run at least 3 Per Core and the CPU to run 3 or 4 Regular Wu's on a Quad & up to 8 Regular Wu's' on a i7 ...

<avg_ncpus>0.05</avg_ncpus>
<max_ncpus>1</max_ncpus>
<cmdline>n3</cmdline>

Don't know if they would work for you or not, the last to lines should work as they work on all my Box's running a ATU GPU Capable Card. The Top line is the one I play with, I have it set to anywheres from 1.0 to 0.01 & in between to get the Cards to run at least 3 Per Core and the CPU to run 3 or 4 Regular Wu's on a Quad & up to 8 Regular Wu's' on a i7 ...

<avg_ncpus>0.05</avg_ncpus>
<max_ncpus>1</max_ncpus>
<cmdline>n3</cmdline>

Had a look at your hosts PoorBoy and yup looks like your method works :) Thanks for the input, I'll give it a bash when I get home. What config are you using of OS/BOINC/Catalyst? XP/6.6.20/9.5?

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What config are you using of OS/BOINC/Catalyst? XP/6.6.20/9.5?

Winblows XP Pro SP2/BOINC Client v6.6.20/ ATI Catalyst v8.12 ... I use that on all my ATI Box's and NVIDIA except for the Video Driver of course ...

8.12 is recognising your 4850X2? How weird, maybe I should redownload. My normal Cat 8.12/XP32 installation that I carry on a USB has worked flawlessly, but wouldn't recognise the X2...

Also, any reason for not upgrading to SP3? (If it works, don't fix it? =D)

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No No, that was my problem for a Day+, I was trying all the Drivers & couldn't get the Card to run for more than a few Minutes without getting the VPU Reset.

I'm assuming it's a Sapphire 4850 X2, if it is use the Driver (8.12)on the CD but don't let the Cd Automatically install the Drivers.

1. Let the CD Spin up & once it has exit the CD
2. Use Explore to explore the CD
3. Go to the Driver Folder & Double Click on the Setup Exec
4. This lets you choose what to install unlike if the CD does the Install it installs every thing & gives you no choice on what or what not to install.

Also, any reason for not upgrading to SP3? (If it works, don't fix it? =D)

I wouldn't Upgrade to SP2 if I didn't have to to get some things to work, I Install the OS, Shut the Fire wall off, Deny access to the Registry and forget it, never have done any Upgrading after that on any of my Box's, not even my Main one.

Had a play around - the drivers on my Sapphire install CD aren't recognised by GPU-Z as any version of Catalyst, however RivaTuner sees them as Cat 8.10. Needless to say MW doesn't like them.

Went to the Sapphire website, got their 8.12 (I still find it weird that the 8.12 from ATi doesnt recognise the card, but oh well). MW is now computing again, but still on 50% of each GPU. Tried the 0.05 CPU/n3 settings too, still no dice. Host is still taking 2x as long as a single 4850 to do WU.

Only thing left is to go to 6.6.20, which will be the task this evening, or do it without Crossfire and hopefully VPU wont set in again.

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I don't have Crossfire Enabled but I do have 1 Dummy Plug on the Top Card & 2 Dummy Plugs on the Bottom Card, Card 1 (Top) & 2 (Bottom} as the CCC sees them ...

Awesome ta - did my method of enabling the 2nd GPU to extend my desktop to that GPU then making it my primary monitor. Switch over the cable in the back, and both GPUs are seen without the need for a dummy plug.

Both GPUs running at 675/1000, between 60-90% GPU load depending on the WU. 55cred WU takes 65 secs, a 74 cred WU takes around 100. A nice and toasty 74ºC in the middle of the day in a warm UK.

I switched the settings to

<avg_ncpus>1</avg_ncpus>
<max_ncpus>1</max_ncpus>
<cmdline>n1</cmdline>

Just incase the slow CPU (x2-5050e) was detrimental and the WUs kept flicking between cores.

Many thanks for the info Poorboy, great help :) Now I just got offered a very nice 4870X2 dirt cheap...

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Borandi, please explain in detail what your doing to not have to use a Dummy Plug ... Thanks

In Win XP:

Right click Desktop
Goto Properties
Click Settings
Goto Second Monitor
Click 'Extend Desktop to this Monitor'
Click 'Make Monitor Primary Desktop'
Click Apply
You'll look like you have a blank screen, or just icons. If icons, select them all, then drag them off screen to the right.
Unplug the VGA/DVI cable from the first card, and plug into the second.

Now you have a desktop, with the mouse able to go off screen to the left. Both GPUs are active and function normally.

I believe this works because the PC will always activate the first GPU in the system, and now the 2nd is activated because it is the primary monitor.

I doubt this method works with 3 GPUs in one system, but it definitely works with two.

Edit - you may be able to do three. Have the two working, then go to the third. Click 'extend the desktop to this monitor', then hover over Apply. Then put the VGA cable into the 3rd GPU. Then click. It may work, I'll try it later :)

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That may work for you but for me it may mean a complete re-installation of the OS, I'm locked out of even getting back into Windows right now on a Box that was working fine before I tried your method.

PS: I'm back in Windows now, put a different Card in, Single Core verses X2 Core & it went back into Windows. I should be able to get it straightened out now. I'll just use the Dummy Plugs for safetys sake ...

Do you not see a screen when putting the DVI cable in on any of the ports? That's odd, it should show on at least two.

If all seems borked, it might not need a new OS installation. Just boot up the comp with one card in, sort the display out, then put the other cards back in.

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I'll just use the Dummy Plugs for safetys sake ...

Whatever works :) I should prob get some 70 ohm resistors and make some rather than doing this software faff =D

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It seemed to work when trying 2 Cards but when I went to the 3'rd card was when everything got messed up. I had a screen & even Icon's but the Taskbar was gone on all 3 Screens, then when I rebooted it wouldn't go back into Windows. I have the X2 Card back up & running okay, now to just shut down & put the other single core card in & install the drivers for it. Weird, it's a 4870 but takes different 8.12 Drivers than the 4850 X2 does, whatever floats ATI's Boat I guess.