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Video card not being detected by monitor after switch

By Rysol
Oct 16, 2011
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  1. after purchasing 2 new xfx radeon hd 6970, to run in crossfire, for optimal gaming, my monitor wont detect the two cards. I have tried placing the old card back in and it responds just fine to that one. With the new cards in, everything sounds like it boots and all the indicator leds on my motherboard show up just fine.

    this is the exact video card im trying to use:

    XFX HD-697A-CNDC Radeon HD 6970 2GB 256-bit GDDR5 PCI Express 2.1 x16 HDCP Ready CrossFireX Support Video Card with Eyefinity

    this is what im running besides the xfx:

    AMD Phenom II X6 1090T Black Edition (125W) Six Core Socket AM3, 3.2GHz, 9Mb Cache, 2000MHz HT, 45nm

    Asus M4A89TD PRO/USB3 Socket AM3 AMD 890FX + SB850 Chipset DDR3 2000(O.C.)/1600/1333/1066Mhz 2x PCI-Express 2.0 x16 8-Channel HD Audio GigaLAN 2x USB3.0+12x USB2.0 6x SATA 6Gb/s ATX

    Cooler Master Silent Pro M850 Modular 850W Power Supply

    Corsair XMS3 Classic 8GB (2x4GB) DDR3 2000MHz CL9 DIMMs, Optimized for Core i7, i5 and Core 2 / AMD Phenom II times 2

    Hitachi Deskstar 7K3000 2TB 3.5" SATA3 6Gb/s 7200rpm 64MB Cache OEM

    LG GH24LS70 Black SATA Lightscribe DVD-Writer 24xDVD+R/-R 8xDVD+RW/6xDVD-RW 16xDVD+R DL 12xDVD-R DL 48x CD-R 32xCD-RW OEM

    Scythe NINJA 3 8 Heat Pipes CPU Cooler for Intel Socket 775/1366/1156 & AMD Socket AM2/AM2+/AM3
     
  2. DKRON

    DKRON TS Enthusiast Posts: 559   +11

    take out one of the graphics cards and see if it works, your monitor only needs to detect the one card that it is plugged into so its not a crossfire problem
     
  3. Rysol

    Rysol TS Rookie Topic Starter

    yea my first problem is getting the graphics cards to respond in the first place
     
  4. DKRON

    DKRON TS Enthusiast Posts: 559   +11

    so you have tried only working one of the cards?
     
  5. Rysol

    Rysol TS Rookie Topic Starter

    yep, still nothing
     
  6. DKRON

    DKRON TS Enthusiast Posts: 559   +11

    and you have run all the drivers from the cd which came with the card?
     
  7. Rysol

    Rysol TS Rookie Topic Starter

    all of them, even the device manager wouldn't recognize the cards either
     
  8. DKRON

    DKRON TS Enthusiast Posts: 559   +11

    hmm that is very weird, open your case and when you turn it on see if the cards power up (fan starts spinning)
     
  9. Rysol

    Rysol TS Rookie Topic Starter

    yep, and the leds on the mother board light up as well indicating that they are on and responding
     
  10. DKRON

    DKRON TS Enthusiast Posts: 559   +11

    the motherboard LED's don't really tell you anything about the graphics, there must be a power shortage going to the card/s they use 2x 6 pins yea?
     
  11. Rysol

    Rysol TS Rookie Topic Starter

    yea they do
     
     
  12. DKRON

    DKRON TS Enthusiast Posts: 559   +11

    just looked up the spec for them and some bad news, 1 uses a minimum 650w PSU which means your 850w will be on the limit to power both cards
     
  13. Rysol

    Rysol TS Rookie Topic Starter

    think my power supply isnt putting out enough power?
     
  14. DKRON

    DKRON TS Enthusiast Posts: 559   +11

    it could explain everything if its not handling the cards it won't fully power either card, it does mention on the coolermaster website that its not crossfire ready but does say SLI ready so they should work the same way anyway, would try different configurations like putting one card in the second PCIe 8x slot and different 6pin powers
     
  15. ---agissi---

    ---agissi--- TechSpot Paladin Posts: 2,384   +15

    I'd try testing the cards in another computer with adequate power that way you can make sure they work at all. I would suspect its your PSU, but the cards could have been damaged by the low power, however I'd suspect they are OK.
     
  16. Rysol

    Rysol TS Rookie Topic Starter

    it turns out that the video card requires both an 8pin and 6pin power cable not just one
     
  17. DKRON

    DKRON TS Enthusiast Posts: 559   +11

    thats why i asked you if it used 2 6pins, good to see it works now atleast
     


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