# Problems w/ Second GPU on CentOS **URL:** \ **Category:** CUDA Programming and Performance\ **Created:** [May 31, 2009, 2:22am UTC](https://forums.developer.nvidia.com/t/problems-w-second-gpu-on-centos/9808 "2009-05-31T02:22:51Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![jmcinerney6](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/jmcinerney6/32/60547_2.png) [@jmcinerney6](https://forums.developer.nvidia.com/u/jmcinerney6)\ **Post date:** [May 31, 2009, 2:22am UTC](https://forums.developer.nvidia.com/t/problems-w-second-gpu-on-centos/9808/1 "2009-05-31T02:22:51Z")
Hi. I have a CentoOS machine with 2 GeForce GTX 285s. I am only able to get one of the cards to work. I have swapped cards and the card in the top slot works each time, so I’m pretty sure the cards are okay. I have attached a monitor to both cards, but the second card, again, doesn’t work. Any clues about how I might get the second card going? Are there things I should try? I have read all about getting multiple monitors going with the two cards, but I don’t think I am there yet. Right now I’d just like to be able to run CUDA kernels on both cards. I have the output of deviceQuery below. I also included the output of scanpci.-v. John McInerney [jmcinerney6@gmail.com](mailto:jmcinerney6@gmail.com) * * * The output of deviceQuery: There is 1 device supporting CUDA Device 0: “GeForce GTX 285” Major revision number: 1 Minor revision number: 3 Total amount of global memory: 2146762752 bytes Number of multiprocessors: 30 Number of cores: 240 Total amount of constant memory: 65536 bytes Total amount of shared memory per block: 16384 bytes Total number of registers available per block: 16384 Warp size: 32 Maximum number of threads per block: 512 Maximum sizes of each dimension of a block: 512 x 512 x 64 Maximum sizes of each dimension of a grid: 65535 x 65535 x 1 Maximum memory pitch: 262144 bytes Texture alignment: 256 bytes Clock rate: 1.48 GHz Concurrent copy and execution: Yes Test PASSED The output of scanpci: pci bus 0x0002 cardnum 0x00 function 0x00: vendor 0x10de device 0x05b1 nVidia Corporation Device unknown STATUS 0x0010 COMMAND 0x0504 CLASS 0x06 0x04 0x00 REVISION 0xa3 HEADER 0x01 LATENCY 0x00 PRIBUS 0x02 SECBUS 0x03 SUBBUS 0x05 SECLT 0x00 SECSTATUS 0x0000 IOBASE 0x0000f000 IOLIM 0x00000fff NOPREFETCH\_MEMBASE 0xfff00000 MEMLIM 0x000fffff PREFETCH\_MEMBASE 0x00000000fff00000 MEMLIM 0x00000000000fffff NO\_FAST\_B2B NO\_SEC\_BUS\_RST NO\_M\_ABRT NO\_VGA\_EN NO\_ISA\_EN SERR\_EN PERR\_EN pci bus 0x0003 cardnum 0x00 function 0x00: vendor 0x10de device 0x05b1 nVidia Corporation Device unknown STATUS 0x0010 COMMAND 0x0504 CLASS 0x06 0x04 0x00 REVISION 0xa3 HEADER 0x01 LATENCY 0x00 PRIBUS 0x03 SECBUS 0x04 SUBBUS 0x04 SECLT 0x00 SECSTATUS 0x0000 IOBASE 0x0000f000 IOLIM 0x00000fff NOPREFETCH\_MEMBASE 0xfff00000 MEMLIM 0x000fffff PREFETCH\_MEMBASE 0x00000000fff00000 MEMLIM 0x00000000000fffff NO\_FAST\_B2B NO\_SEC\_BUS\_RST NO\_M\_ABRT NO\_VGA\_EN NO\_ISA\_EN SERR\_EN PERR\_EN pci bus 0x0003 cardnum 0x02 function 0x00: vendor 0x10de device 0x05b1 nVidia Corporation Device unknown STATUS 0x0010 COMMAND 0x0504 CLASS 0x06 0x04 0x00 REVISION 0xa3 HEADER 0x01 LATENCY 0x00 PRIBUS 0x03 SECBUS 0x05 SUBBUS 0x05 SECLT 0x00 SECSTATUS 0x0000 IOBASE 0x0000f000 IOLIM 0x00000fff NOPREFETCH\_MEMBASE 0xfff00000 MEMLIM 0x000fffff PREFETCH\_MEMBASE 0x00000000fff00000 MEMLIM 0x00000000000fffff NO\_FAST\_B2B NO\_SEC\_BUS\_RST NO\_M\_ABRT NO\_VGA\_EN NO\_ISA\_EN SERR\_EN PERR\_EN pci bus 0x0006 cardnum 0x00 function 0x00: vendor 0x10de device 0x05e3 nVidia Corporation Device unknown CardVendor 0x3842 card 0x1185 (Card unknown) STATUS 0x0010 COMMAND 0x0007 CLASS 0x03 0x00 0x00 REVISION 0xa1 BIST 0x00 HEADER 0x00 LATENCY 0x00 CACHE 0x00 BASE0 0xfa000000 addr 0xfa000000 MEM BASE1 0x00000000d000000c addr 0x00000000d0000000 MEM PREFETCHABLE 64BIT BASE3 0x00000000f8000004 addr 0x00000000f8000000 MEM 64BIT BASE5 0x0000ac01 addr 0x0000ac00 I/O MAX\_LAT 0x00 MIN\_GNT 0x00 INT\_PIN 0x01 INT\_LINE 0x0f BYTE\_0 0x42 BYTE\_1 0x38 BYTE\_2 0x85 BYTE\_3 0x11 ---
**Author:** ![tmurray](https://developer.download.nvidia.com/images/forums/profile-default-devtalk-84.png) [@tmurray](https://forums.developer.nvidia.com/u/tmurray)\ **Post date:** [May 31, 2009, 2:55am UTC](https://forums.developer.nvidia.com/t/problems-w-second-gpu-on-centos/9808/2 "2009-05-31T02:55:56Z")
sounds like a motherboard or power supply problem to me. are you sure both the motherboard and power supply are capable of handling 2 285s? ---
**Author:** ![pvonkaenel](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/pvonkaenel/32/9806_2.png) [@pvonkaenel](https://forums.developer.nvidia.com/u/pvonkaenel)\ **Post date:** [June 4, 2009, 8:05pm UTC](https://forums.developer.nvidia.com/t/problems-w-second-gpu-on-centos/9808/3 "2009-06-04T20:05:22Z")
I just got CentOS 5.3 installed and using the latest beta drivers and Toolkit 2.2 I’m able to see both my Quadro FX 1700 and GeForce 285 GTX. It’s not your exact situation, but pretty close. Therefore, tmurray is probably correct (as usual). Peter