2nd Dedicated Folding GPU?

Sasquatch

I have an unused HD 6450 2GB just sitting in my storage closet. With the latest versions of the Folding software, I'm wondering if it's possible to use that GPU as a dedicated folding device?
I know it's not the most powerful of GPUs or anything and wouldn't serve me any purpose otherwise, but I figured it'd be better than just letting it sit in the closet.

My ideal would be that even when I'm actively using my machine, that GPU could still be folding slowly in the background, and my primary GPU would only kick in after the machine was idle.

Any Gurus knowing the ins & outs of the Folding software able to tell me if this is possible or not?
About to head for work & the thought just hit me so haven't had time to look anything up or do physical testing on it.

sverek · 10-09-2013, 04:04 | posts: 1,423 | Location: Japan, Soka

In my experience it was straight-forward:
Just stick your HD 6450 to any open PCI-exp slot.

In FAHClient click configure, add GPU. You will probably have both GPUs folding. Just pause your main GPU when you need use it.

iancook221188 · 10-09-2013, 07:50 | posts: 1,491 | Location: uk

what your primary GPU going to be if it an nvidia there could be some conflict?

PantherX · 10-09-2013, 15:56 | posts: 1,215

Based on the PC Specs in your profile, you have an AMD GPU. Thus, it won't be conflict when you install the other AMD GPU

Do you already have the F@H V7 client installed on your system? If not, then you may want to install (http://folding.stanford.edu/home/gui...install-guide/) it. Regardless of what V7 version you are running, just make sure that you have the following configured in your GPU Slots, make sure that you open Advanced Control (AKA FAHControl) -> Configure -> Slots Tab -> GPU -> Under the Extra slot Options, enter the following:
Name: client-type
Value: advanced
With the above configuration, you will be assigned FahCore_17 WUs which are better optimized for (most) AMD GPUs.

If you are using V7.3.6, then please note the following:
1) In Advanced Control, you have to right-click the Slots to get individual slot options.
2) If you want, you can configure the Primary GPU to automatically fold when your system is idle, no need to remember to pause/unpause the GPU manually.

Sasquatch · 10-10-2013, 19:21 | posts: 372 | Location: Montana

Quote:

Originally Posted by PantherX

Based on the PC Specs in your profile, you have an AMD GPU. Thus, it won't be conflict when you install the other AMD GPU

Do you already have the F@H V7 client installed on your system? If not, then you may want to install (http://folding.stanford.edu/home/gui...install-guide/) it. Regardless of what V7 version you are running, just make sure that you have the following configured in your GPU Slots, make sure that you open Advanced Control (AKA FAHControl) -> Configure -> Slots Tab -> GPU -> Under the Extra slot Options, enter the following:
Name: client-type
Value: advanced
With the above configuration, you will be assigned FahCore_17 WUs which are better optimized for (most) AMD GPUs.

If you are using V7.3.6, then please note the following:
1) In Advanced Control, you have to right-click the Slots to get individual slot options.
2) If you want, you can configure the Primary GPU to automatically fold when your system is idle, no need to remember to pause/unpause the GPU manually.

OK, I've got this going. I'm just wondering is there a way to make the 6450 fold even when the system is in use? Nothing else is using this GPU so it should already be idle, but it seems possibly linked with the 7850.
The F@H client shows:
ID/GPU:0:AMD Radeon HD 6450
ID/GPU:1:Radeon HD 7800
ID/CPU:5 <- (this is an AMD FX-6300)
Both the GPUs say "Paused:Waiting for idle. The CPU is currently Running. My client is set to Medium power.
In the AMD Catalyst Control panel > Information > Hardware: shows the 7850 as the Primary adapter, and the 6450 as Disabled.

Any other ideas or extra slots configs I might be able to use?

Sasquatch · 10-11-2013, 00:51 | posts: 372 | Location: Montana

Update: Was out running errands today, and when I get back, it looks like both GPUs are working the same work order. But now neither of them pauses when I fire up a game. I had to manually pause the 7850, but the 6450 still seems to be folding.....
Any tips?

PantherX · 10-11-2013, 02:11 | posts: 1,215

Can you please post the initial section of your log which shows the system configuration and the F@H Configuration. I assume that you are running the latest WHQL Drivers from AMD, right?

Sasquatch · *Last edited by PantherX; 10-11-2013 at 17:07.*

Running Catalyst 13.9.
Here's the log: (Hope it's the right stuff)

Code:

*********************** Log Started 2013-10-10T19:41:46Z ***********************
19:41:46:************************* Folding@home Client *************************
19:41:46:      Website: http://folding.stanford.edu/
19:41:46:    Copyright: (c) 2009-2013 Stanford University
19:41:46:       Author: Joseph Coffland <joseph@cauldrondevelopment.com>
19:41:46:         Args: 
19:41:46:       Config: C:/Users/Kc7vwc/AppData/Roaming/FAHClient/config.xml
19:41:46:******************************** Build ********************************
19:41:46:      Version: 7.3.6
19:41:46:         Date: Feb 18 2013
19:41:46:         Time: 15:25:17
19:41:46:      SVN Rev: 3923
19:41:46:       Branch: fah/trunk/client
19:41:46:     Compiler: Intel(R) C++ MSVC 1500 mode 1200
19:41:46:      Options: /TP /nologo /EHa /Qdiag-disable:4297,4103,1786,279 /Ox -arch:SSE
19:41:46:               /QaxSSE2,SSE3,SSSE3,SSE4.1,SSE4.2 /Qopenmp /Qrestrict /MT /Qmkl
19:41:46:     Platform: win32 XP
19:41:46:         Bits: 32
19:41:46:         Mode: Release
19:41:46:******************************* System ********************************
19:41:46:          CPU: AMD FX(tm)-6300 Six-Core Processor
19:41:46:       CPU ID: AuthenticAMD Family 21 Model 2 Stepping 0
19:41:46:         CPUs: 6
19:41:46:       Memory: 15.90GiB
19:41:46:  Free Memory: 14.53GiB
19:41:46:      Threads: WINDOWS_THREADS
19:41:46:  Has Battery: false
19:41:46:   On Battery: false
19:41:46:   UTC offset: -6
19:41:46:          PID: 2920
19:41:46:          CWD: C:/Users/Kc7vwc/AppData/Roaming/FAHClient
19:41:46:           OS: Windows 7 Home Premium
19:41:46:      OS Arch: AMD64
19:41:46:         GPUs: 2
19:41:46:        GPU 0: ATI:4 Caicos [AMD RADEON HD 6450]
19:41:46:        GPU 1: ATI:5 PITCAIRN PRO [Radeon HD 7800 Series]
19:41:46:         CUDA: Not detected
19:41:46:Win32 Service: false
19:41:46:***********************************************************************
19:41:46:<config>
19:41:46:  <!-- Folding Core -->
19:41:46:  <cpu-usage v='50'/>
19:41:46:
19:41:46:  <!-- Network -->
19:41:46:  <proxy v=':8080'/>
19:41:46:
19:41:46:  <!-- User Information -->
19:41:46:  <passkey v='********************************'/>
19:41:46:  <team v='224384'/>
19:41:46:  <user v='Kc7vwc'/>
19:41:46:
19:41:46:  <!-- Folding Slots -->
19:41:46:  <slot id='0' type='GPU'>
19:41:46:    <client-type v='advanced'/>
19:41:46:  </slot>
19:41:46:  <slot id='1' type='GPU'>
19:41:46:    <client-type v='advanced'/>
19:41:46:  </slot>
19:41:46:  <slot id='2' type='CPU'/>
19:41:46:</config>
19:41:46:Trying to access database...
19:41:46:Successfully acquired database lock
19:41:46:Enabled folding slot 00: PAUSED gpu:0:Caicos [AMD RADEON HD 6450] (waiting for idle)
19:41:46:Enabled folding slot 01: PAUSED gpu:1:PITCAIRN PRO [Radeon HD 7800 Series] (waiting for idle)
19:41:46:Enabled folding slot 02: READY cpu:5
19:41:46:WU00:FS02:Starting
19:41:46:WU00:FS02:Running FahCore: "C:\Program Files (x86)\FAHClient/FAHCoreWrapper.exe" C:/Users/Kc7vwc/AppData/Roaming/FAHClient/cores/www.stanford.edu/~pande/Win32/AMD64/Core_a3.fah/FahCore_a3.exe -dir 00 -suffix 01 -version 703 -lifeline 2920 -checkpoint 15 -cpu 50 -np 5
19:41:46:WU00:FS02:Started FahCore on PID 1056
19:41:46:WU00:FS02:Core PID:2372
19:41:46:WU00:FS02:FahCore 0xa3 started
19:41:47:WU00:FS02:0xa3:
19:41:47:WU00:FS02:0xa3:*------------------------------*
19:41:47:WU00:FS02:0xa3:Folding@Home Gromacs SMP Core
19:41:47:WU00:FS02:0xa3:Version 2.27 (Dec. 15, 2010)
19:41:47:WU00:FS02:0xa3:
19:41:47:WU00:FS02:0xa3:Preparing to commence simulation
19:41:47:WU00:FS02:0xa3:- Ensuring status. Please wait.
19:41:56:WU00:FS02:0xa3:- Looking at optimizations...
19:41:56:WU00:FS02:0xa3:- Working with standard loops on this execution.
19:41:56:WU00:FS02:0xa3:- Previous termination of core was improper.
19:41:56:WU00:FS02:0xa3:- Going to use standard loops.
19:41:56:WU00:FS02:0xa3:- Files status OK
19:41:56:WU00:FS02:0xa3:- Expanded 3848901 -> 4392432 (decompressed 114.1 percent)
19:41:56:WU00:FS02:0xa3:Called DecompressByteArray: compressed_data_size=3848901 data_size=4392432, decompressed_data_size=4392432 diff=0
19:41:57:WU00:FS02:0xa3:- Digital signature verified
19:41:57:WU00:FS02:0xa3:
19:41:57:WU00:FS02:0xa3:Project: 8581 (Run 1, Clone 0, Gen 47)
19:41:57:WU00:FS02:0xa3:
19:41:57:WU00:FS02:0xa3:Entering M.D.
19:42:03:WU00:FS02:0xa3:Using Gromacs checkpoints
19:42:03:WU00:FS02:0xa3:Mapping NT from 5 to 5 
19:42:05:WU00:FS02:0xa3:Resuming from checkpoint
19:42:05:WU00:FS02:0xa3:Verified 00/wudata_01.log
19:42:05:WU00:FS02:0xa3:Verified 00/wudata_01.trr
19:42:05:WU00:FS02:0xa3:Verified 00/wudata_01.edr
19:42:06:WU00:FS02:0xa3:Completed 11430 out of 500000 steps  (2%)
19:52:26:Saving configuration to config.xml
19:52:26:<config>
19:52:26:  <!-- Folding Core -->
19:52:26:  <cpu-affinity v='true'/>
19:52:26:  <cpu-usage v='50'/>
19:52:26:
19:52:26:  <!-- Network -->
19:52:26:  <proxy v=':8080'/>
19:52:26:
19:52:26:  <!-- User Information -->
19:52:26:  <passkey v='********************************'/>
19:52:26:  <team v='224384'/>
19:52:26:  <user v='Kc7vwc'/>
19:52:26:
19:52:26:  <!-- Folding Slots -->
19:52:26:  <slot id='0' type='GPU'>
19:52:26:    <client-type v='advanced'/>
19:52:26:  </slot>
19:52:26:  <slot id='1' type='GPU'>
19:52:26:    <client-type v='advanced'/>
19:52:26:  </slot>
19:52:26:  <slot id='2' type='CPU'/>
19:52:26:</config>
19:55:02:FS02:Shutting core down
19:55:02:Saving configuration to config.xml
19:55:02:<config>
19:55:02:  <!-- Folding Core -->
19:55:02:  <cpu-affinity v='true'/>
19:55:02:  <cpu-usage v='80'/>
19:55:02:
19:55:02:  <!-- Network -->
19:55:02:  <proxy v=':8080'/>
19:55:02:
19:55:02:  <!-- User Information -->
19:55:02:  <passkey v='********************************'/>
19:55:02:  <team v='224384'/>
19:55:02:  <user v='Kc7vwc'/>
19:55:02:
19:55:02:  <!-- Folding Slots -->
19:55:02:  <slot id='0' type='GPU'>
19:55:02:    <client-type v='advanced'/>
19:55:02:  </slot>
19:55:02:  <slot id='1' type='GPU'>
19:55:02:    <client-type v='advanced'/>
19:55:02:  </slot>
19:55:02:  <slot id='2' type='CPU'/>
19:55:02:</config>

Mod Edit: Added Code Tags - PantherX

PantherX · 10-11-2013, 17:20 | posts: 1,215

Okay, with the latest WHQL Driver version, you should be able to fold FahCore_17 WUs without any issue

Regarding your configuration, here are a few observations:
1) Remove the cpu-affinity. In most cases, it does more harm than good unless it is properly configured by third-party applications.
2) Remove the cpu-usage since you are running SMP WUs which doesn't follow this rule.
3) Since you want your HD 6450 to fold 24/7, you have to add the following:
- GPU Slot 0: <power v='full'/>
- GPU Slot 1: <power v='idle'/>
- CPU Slot 3: <power v='full'/> OR <power v='idle'/> it depends if you want the CPU to use 5 CPUs 24/7 or only when the system is idle. Do note that if you want the CPU Slot to use less than 5 CPUs, you can configure it according to your needs.

Hopefully, once you have done all of above tweaks, please restart the system (or the FAHClient at least) and everything should work out fine. If not, please post a new log and we can see what went wrong.

Sasquatch · 10-11-2013, 22:48 | posts: 372 | Location: Montana

OK, so I'm pretty sure I added the Power tags in the wrong spot. I tried adding them to the GPU slots, but the software kept saying invalid name for that option. Then I was able to add them to the Expert > Extra Core Options, but on a fresh boot, the F@H software shows the CPU folding, but both GPUs are Paused:waiting for idle.
Here's the current log:

Code:

*********************** Log Started 2013-10-11T20:30:27Z ***********************
20:30:27:************************* Folding@home Client *************************
20:30:27:      Website: http://folding.stanford.edu/
20:30:27:    Copyright: (c) 2009-2013 Stanford University
20:30:27:       Author: Joseph Coffland <joseph@cauldrondevelopment.com>
20:30:27:         Args: 
20:30:27:       Config: C:/Users/Kc7vwc/AppData/Roaming/FAHClient/config.xml
20:30:27:******************************** Build ********************************
20:30:27:      Version: 7.3.6
20:30:27:         Date: Feb 18 2013
20:30:27:         Time: 15:25:17
20:30:27:      SVN Rev: 3923
20:30:27:       Branch: fah/trunk/client
20:30:27:     Compiler: Intel(R) C++ MSVC 1500 mode 1200
20:30:27:      Options: /TP /nologo /EHa /Qdiag-disable:4297,4103,1786,279 /Ox -arch:SSE
20:30:27:               /QaxSSE2,SSE3,SSSE3,SSE4.1,SSE4.2 /Qopenmp /Qrestrict /MT /Qmkl
20:30:27:     Platform: win32 XP
20:30:27:         Bits: 32
20:30:27:         Mode: Release
20:30:27:******************************* System ********************************
20:30:27:          CPU: AMD FX(tm)-6300 Six-Core Processor
20:30:27:       CPU ID: AuthenticAMD Family 21 Model 2 Stepping 0
20:30:27:         CPUs: 6
20:30:27:       Memory: 15.90GiB
20:30:27:  Free Memory: 14.44GiB
20:30:27:      Threads: WINDOWS_THREADS
20:30:27:  Has Battery: false
20:30:27:   On Battery: false
20:30:27:   UTC offset: -6
20:30:27:          PID: 2976
20:30:27:          CWD: C:/Users/Kc7vwc/AppData/Roaming/FAHClient
20:30:27:           OS: Windows 7 Home Premium
20:30:27:      OS Arch: AMD64
20:30:27:         GPUs: 2
20:30:27:        GPU 0: ATI:4 Caicos [AMD RADEON HD 6450]
20:30:27:        GPU 1: ATI:5 PITCAIRN PRO [Radeon HD 7800 Series]
20:30:27:         CUDA: Not detected
20:30:27:Win32 Service: false
20:30:27:***********************************************************************
20:30:27:<config>
20:30:27:  <!-- Folding Slot Configuration -->
20:30:27:  <extra-core-args v='GPU Slot 0: &lt;power v=&apos;full&apos;/&gt; GPU Slot 1: &lt;power v=&apos;idle&apos;/&gt; CPU Slot 3: &lt;power v=&apos;idle&apos;/&gt;'/>
20:30:27:
20:30:27:  <!-- Network -->
20:30:27:  <proxy v=':8080'/>
20:30:27:
20:30:27:  <!-- User Information -->
20:30:27:  <passkey v='********************************'/>
20:30:27:  <team v='224384'/>
20:30:27:  <user v='Kc7vwc'/>
20:30:27:
20:30:27:  <!-- Folding Slots -->
20:30:27:  <slot id='0' type='GPU'>
20:30:27:    <client-type v='advanced'/>
20:30:27:  </slot>
20:30:27:  <slot id='1' type='GPU'>
20:30:27:    <client-type v='advanced'/>
20:30:27:  </slot>
20:30:27:  <slot id='2' type='CPU'>
20:30:27:    <cpus v='-1'/>
20:30:27:  </slot>
20:30:27:</config>
20:30:27:Trying to access database...
20:30:27:Successfully acquired database lock
20:30:27:Enabled folding slot 00: PAUSED gpu:0:Caicos [AMD RADEON HD 6450] (waiting for idle)
20:30:27:Enabled folding slot 01: PAUSED gpu:1:PITCAIRN PRO [Radeon HD 7800 Series] (waiting for idle)
20:30:27:Enabled folding slot 02: READY cpu:5
20:30:27:WU00:FS02:Starting
20:30:27:WU00:FS02:Running FahCore: "C:\Program Files (x86)\FAHClient/FAHCoreWrapper.exe" C:/Users/Kc7vwc/AppData/Roaming/FAHClient/cores/www.stanford.edu/~pande/Win32/AMD64/Core_a3.fah/FahCore_a3.exe -dir 00 -suffix 01 -version 703 -lifeline 2976 -checkpoint 15 -np 5 GPU Slot 0: <power v='full'/> GPU Slot 1: <power v='idle'/> CPU Slot 3: <power v='idle'/>

So where did I goof up at? Thanks for any advice & sorry to be a pain.

PantherX · 10-12-2013, 04:11 | posts: 1,215

Humm... Maybe I goofed up, try this setting:

1) Remove the extra-core-arg
2) Make sure that the power slider is set to full
3) Under GPU 1 (Your primary GPU), add this so the slot:
<idle v='true'/>

Restart the system and I believe that it should work. Sorry for any inconvenience caused by this.

Sasquatch · *Last edited by Sasquatch; 10-12-2013 at 06:02.*

When you say under the GPU1 to add something, where is that option? The only place I can add a single line of text is the Configuration > Expert > Extra Core Options
Anything I try under the Slots tab, I have to have a name & value, and anything I put in the name area the software says is not valid.
Just added the "3) Under GPU 1 (Your primary GPU), add this so the slot:
<idle v='true'/>" to the Extra Core Options, with F@H set to Full. On reboot, everything was folding immediately.
Going to now try using only the "GPU Slot 1: <power v='idle'/>" with software on full.
BRB.

Update: None of the options seems to work. So I tried deleting the 7850 from F@H. Now the 6450 is showing Paused:waiting for idle.
I did try adding the GPU Slot 0: <power v='full'/> option to the Extra Core but it still shows waiting for idle.
Thinking I may just have to set it for full to let the 6450 fold 24/7 & not have the 7850 in the F@H software at all.
But for now it's off to bed & I'll fight with it again in the morning.

PantherX · 10-12-2013, 16:02 | posts: 1,215

Oh, I am sorry for not elaborating! Under the GPU 1 Slot, you had to do this:
Name: idle
Value: true

With the Power Slider set to full, this would mean that your HD 7850 will only fold when the system is idle but your HD 6450 and CPU will be folding 24/7. If you want your CPU to also fold when only idle, just add the above option to the CPU Slot too.

Third times the charm... I hope

Sasquatch · 10-12-2013, 22:23 | posts: 372 | Location: Montana

You're a genius!
That seems to have nailed it.

PantherX · 10-13-2013, 04:23 | posts: 1,215

Thanks. Glad to hear that everything is folding perfectly for you

Sasquatch · 10-18-2013, 19:59 | posts: 372 | Location: Montana

So update & question: The configuration seems to be working great, but I'm wondering about the 6450's performance and streamlining everything a bit.
Right now, I have everything else paused and F@H is showing the 6450 at 80 - 150 PPD and 55+ days to complete the current WU (right term?). I currently have the advanced client attributed to both GPUs. Is this the optimal setting for the 6450?
Also, I've been playing a few older games that are a little more CPU attuned & they've been kinda choppy. What would I need to set in the options to tone down the CPU folding a little?
There's the option in the CPU slot for thread usage. I just tried setting this to 4, and HWiNFO64 software is showing my CPU usage around 94% for all 6 cores - instead of 100% it was before. Is this supposed to limit how many cores F@H is using, or just the % of core usage?

So basically wanting to increase performance of 6450 & streamline CPU folding while playing games.
- With CPU threads set to 4, CPU & 6450 GPU folding right now, I'm at 3621 PPD. Is this on par?

PantherX · 10-18-2013, 21:29 | posts: 1,215

I am not sure about your HD 6450 performance. Maybe you can ask on the official forum. If GPU-Z is showing 100% GPU load on your GPU plus all the frequencies are at normal values, i.e. not down-clocking, then overclocking the GPU would be your only option.

Since you have a hexacore, the following CPU Threads should result in F@H CPU Usage as it is restricting the FahCore to use X CPUs only regardless of how many your system has in total:
2 -> ~33% of your CPU dedicated to CPU Folding
3 -> ~49% of your CPU dedicated to CPU Folding
4 -> ~65% of your CPU dedicated to CPU Folding
5 -> ~82% of your CPU dedicated to CPU Folding

I wouldn't suggest 1 since currently there aren't any WUs (yep, that's the correct term) and 6 since your system isn't dedicated so any CPU cycles taken from CPU folding would result in a non-linear decline in PPD.

The CPU 4 option (or whatever number you use) might take effect with a new WU or a client restart. Your CPU Usage is higher than expected if it was taken during folding only. Maybe you can fire up Task Manager and see what other process (if any) are taking up additional CPU Cycles. Also, are your GPUs processing FahCore_17 WUs or is there FahCore_16 WU also? I think that your CPU might be under performing (that's possible if other processes are taking CPU Cycles from F@H) so try reducing the CPU Count. Also, you may want to post the log to see what Project is running on your CPU. To give you a rough idea, here is what I get from my CPUs:
i7-860 @ 3.8 with CPU:6 -> 9.7K - 12K (Dedicated)
i7-3840QM @ Stock with CPU:4 -> 6.2K - 10K (Non-Dedicated)

Sasquatch · 10-19-2013, 06:10 | posts: 372 | Location: Montana

Update: Have the CPU set to 4 on the threads - and gaming seems fine at that setting so far.
After heading out for errands & stuff tonight, the WU for the 6450 is showing only 9.61 days ETA. So not sure what made the big jump there.
F@H is showing 0x17 WU's for the GPUs & 0xa4 WU's for the CPU.

After all the tinkering, starts & stops, later tonight when I head for bed, I'm just gonna do a system restart to get a fresh log with nothing else going on, then check in the morning.
Thanks for the info so far. Big help for a fun project.

PantherX · 10-19-2013, 14:37 | posts: 1,215

Humm, the "jump" might just actually be when FAHControl/WebControl makes the correct prediction. Sometimes, it takes a couple of frames to get the correct data.

A system restart would ensure that all F@H settings are working as they should, hopefully

yasamoka · 11-16-2013, 17:05 | posts: 3,404 | Location: Lebanon

Nice thread. So guys, I'm trying to make the 2nd GPU only fold 24/7 and leave the first GPU not folding at all. So idle = true doesn't do what I want.

Trying to find a way to do this, but anybody have any suggestions?

Thanks!

iancook221188 · 11-16-2013, 19:41 | posts: 1,491 | Location: uk

you should be able to delete the slot for the gpu you don't want to fold?

PantherX · 11-16-2013, 21:53 | posts: 1,215

iancook221188 is correct. My I suggest that you first set the GPU Slot to finish and once the WU is over, you can proceed to remove the Slot. That way, no WUs are wasted.

sykozis · *Last edited by sykozis; 11-20-2013 at 18:55.*

Quote:

Originally Posted by yasamoka

Nice thread. So guys, I'm trying to make the 2nd GPU only fold 24/7 and leave the first GPU not folding at all. So idle = true doesn't do what I want.

Trying to find a way to do this, but anybody have any suggestions?

Thanks!

When I had the GT640+GTX660, I removed both GPU slots. Then I manually added 1 GPU slot back, and set GPU index to 0. If that folded on the proper card, I left it. If it folded on the wrong card, I changed it to 1. For some reason, F@H couldn't detect my cards properly. Once I knew which one was the GT640 (which I had folding 24/7 for a few months), I left the GPU slot set for that card. In your case, the GPU slot should be set to GPU Index 1 for the second card. The default is -1, which automatically detects the GPUs and will assign WU's to the first GPU it sees. You'll have to change the GPU Index if you want it to use the second card.