PCI E 16x and 8x

I trying to build my own pc. I noticed that My MOB has a PCI E 16x and a PCI E dual 8x. i am going to be using 2 graphics cards. My question is, am i losing speed because the 2nd slot is 8x? do i need to get a MOB that has 2x PCI E slots in order to get full benefit out of my video cards? Ive linked the card if that helps. thank you for your help.

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  1. Ideally you want a motherboard with two PCI-Express x16 slots, or even a x16 and x8. However, the motherboard you linked only has two x8 slots. I'm not sure about the differences in performance; there was an article floating around somewhere...
  2. How much speed loss am i talking about, i spent 600 bucks on 2 video cards, id hate to have screwed that by getting the wrong MOB. I can always send it back when i get it, if its gonna be a real game changer in regards to performance.
  3. depends on the cards but I'm guessing you have dual 6950s from your stated price but even with a 5970 the max performance drop you will see is about 4% no biggy for 6950s it'll be about 1or2%

    If you tell me the vid cards I'll tell you if it'll be bottlenecked
  4. If you have two high-end vid cards Sandy Bridge would be a better choice, albeit more expensive than AMD the intels won't bottleneck the vid-cards the AMD processors might bottleneck but if you know how to overclock you should be fine
  5. http://www.newegg.com/Product/Product.aspx?Item=N82E16814161355

    this is the cards I got.

    I found another MOB for 30 bucks more. if its gonna be huge speed slow down, then shoot it to me strait :) and ill return the other one
  6. no the 6950s should not be bottlenecked too much maybe a 4% framerate reduction max I can't find a link right now but I remember reading a tom's article a while ago about how the reduction wasn't noticeable and how x8/x8 is fine for most cards the 5970 was the only card with a noticeable reduction at x8 due to the fact that it has dual GPUs on one board with 6950s there should be no noticeable reduction thus don't return and keep that board

    All told completely straight up, If I had to I would tell you that board was crap and you should return it and your really dumb but I don't :D
  7. thanks for the info. and thanks for coming from the hip :) Ill keep the board and hope and pray I can actually put this thing together without blowing it up (Im a virgin to this building mess) Anywho, thanks a bunch!
  8. how to build a pc: http://www.tomshardware.com/forum/274745-31-step-step-guide-building

    troubleshooting: http://www.tomshardware.com/forum/261145-31-perform-steps-posting-boot-video-problems

    If you have any questions don't be shy, no question is stupid (excluding ones with obvious google answers)

    READ YOUR MANUALS please don't be cocky about building, you'll get yourself into trouble
  9. To be on the safe-side, make sure to use one of these when you are building your PC--good luck!
  10. And remember half hardware half software

    for windows 7 help: http://www.sevenforums.com/

    for virus help: http://www.bleepingcomputer.com/
  11. actually anti-static bands are a gimmick to prevent static build on a cardboard/wood surface and be in contact with the case when manipulating parts, use it to ground yourself
  12. Personally, I kind of agree, but the industry experts wouldn't.
  13. Ahh the passive attack approach, agree with me and pin the disagreement on a third non-present person

    I will not start a pointless argument about this but if you're gonna disagree do so don't chicken out, if you were incorrect in your last post concede completely, these are the basic rules of opinion
  14. I just was trying to be nice, but fine, jeez...

    You are wrong. ESD is a real danger and does destroy computer components regularly. If you disagree, contact Intel, etc. to let them know that ESD is actually made-up because you (normally) can't see or feel it: http://www.intel.com/Assets/PDF/pkginfo/ch_06.pdf

    "Electrostatic discharge (ESD) costs the electronics industry millions of dollars each year in damaged components, non-functional circuit boards and scrambled or missing information. ESD can occur in the manufacturing, shipping, receiving, and field handling of integrated circuits or computer boards with no visible signs of damage. A malfunction in these components or boards can occur immediately or the apparatus may perform for weeks, months, or even years before an unpredictable and premature breakdown causes a field failure."
  15. WEll this is the stuff I bought I hope it all works together, I think it will. Thanks again for all the answers and I'll be using those guides u linked to help out.

    ~Rosewill RFA-120-BL 120mm 4 Blue LEDs LED Case Fan
    ~G.SKILL 4GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) Dual Channel Kit Desktop Memory Model F3-12800CL9D-4GBNQ
    ~AMD Phenom II X2 560 Black Edition Callisto 3.3GHz Socket AM3 80W Dual-Core Desktop Processor HDZ560WFGMBOX
    ~Rosewill BRONZE Series RBR1000-M 1000W Continuous@40°C, 80Plus Bronze Certified,Modular Cable Design,Active PFC"Compatible ...
    ~Rosewill CHALLENGER Black Gaming ATX Mid Tower Computer Case, comes with Three Fans-1x Front Blue LED 120mm Fan, 1x Top 140mm ...
    ~Western Digital Caviar Green WD20EARS 2TB SATA 3.0Gb/s 3.5" Internal Hard Drive -Bare Drive
    ~ASUS M4A79XTD EVO AM3 AMD 790X ATX AMD Motherboard
    ~HIS H695F2G2M Radeon HD 6950 2GB 256-bit GDDR5 PCI Express 2.1 x16 HDCP Ready CrossFireX Support Video Card with Eyefinity
    ~Microsoft Windows 7 Home Premium 64-bit 1-Pack for System Builders - OEM
    ~ASUS DRW-24B1ST/BLK/B/AS Black SATA 24X DVD Burner - Bulk - OEM
  16. Let me know if you're able to unlock the cores, a triple core would be nice for games

    @Hastibe ESD can be prevented by discharging by touching your case while working on the components, thank you for plain out disagreeing it is much simpler to argue with
  17. Well I went 2 for 2 on the computer builds with no problems what so ever....that I can tell. I was very surprised. I do have one question about ATI Crossfire. How can I be positive that both of my graphics card are being used in tandem? I enabled crossfire in settings, is that all I have to do? when I'm in catalyst control center the speeds and temps are only registering for 1 card, is this because the computer recognizes them as 1 ? thanks for help.
  18. Wow, flamecity!

    You clearly stated that anti static wrist bands are a gimmick, and you couldn't be more wrong. To make things more fun, you were proven wrong with facts and proofs. Don't be so quick to flame, you might get lit up yourself. ESD is real, ESD wristbands prevent it. If you'd like to hold on to your case with one hand the entire time you assemble, feel free. I prefer two hands.

    Your 8x/8x won't be an issue. Is it ideal? No. Will you notice the difference? No.
  19. jack_attack said:
    Wow, flamecity!
    Haha, hardly "flamecity," :sarcastic: in my experience, but sorry for any flame-like contributions!

    joelmartinez, truce? I have a peace offering:
    Anonymous said:
    I just did a build for the first time with an anti static strap two weeks ago and I'll tell you I miss leaning on my case. It makes me feel closer to the components and at one with my developing system. I feel so detached from this new build. I might go rip it all apart and lean on the case and put it all back together.

    This response is from this thread on Tom's--it's still making me giggle. :) Something about grappling with all the pieces while leaning against the case with your shirt off... Just makes you feel close, you know? :D
  20. Okay truce, I was not trying to be rude and I agree ESD is a serious hazard I feel that saving 2.50 and touching your case the entire time is a better idea than spending the cash, I'm just cheap I guess
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