Running 3 Monitors by Installing Second PCI Express Card

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Introduction: Running 3 Monitors by Installing Second PCI Express Card

I wanted to run 3 monitors on my PC but it only had a single video card slot. That meant I could only run 1 video card and a single video card usually only supports 2 monitors. Some high end cards support 3 or more monitors but of course I wanted to do this on the cheap! I'd heard it was possible to install a second video card by cutting most of the pins off a 16x PCI Express card and installing it in a 1x slot. It sounded like a bit of an internet myth but it turned out to be true and has been running in my PC for many months.

The photo below shows the available slots for my motherboard. The blue one on the left is the 16x PCI Express slot that takes a video card. The next 2 slots are the old style PCI slots. Installing a video card in one of these slots would be possible but I don't have one, they can be hard to come by and tend to be very old cards. The 4th much smaller slot there that is labelled "PCIEX1" is the PCI Express 1x card. This is effectively the same as the blue slot except cut short. A video card won't physically fit in this slot because its pins are much longer. However, it is actually possible to simply cut the extra pins off the card and it will work.

Step 1: Marking the Location to Cut

The first step is to obtain a PCI Express video card. Decent cards can be obtained from ebay for around $10. Before cutting anything it's a very good idea to mark the pins that should be cut off. We want to cut all the pins off the larger section of the card except for the first 7 pins. In the second pic here I've used a marker to mark the 8th pin. This pin and everything to the right needs to be cut off.

Step 2: Cutting the Card

The next step is to actually cut the pins off the card. The best tool for this is a Dremel with the mini angle grinder blade. I guess you could use a full size grinder or maybe a hacksaw but I haven't tried either of those. Note that I have created a notch just near the 7th pin. Without this the card doesn't sit fully down into the motherboard. I have also cut off the lug towards the back of the card for clearance. This may be necessary to clear capacitors and other items that might be attached to the motherboard. After cutting the card use a razor blade, screw driver or kitchen knife to clean up the edges along the cut. I did this to dislodge any pieces of metal that might be hanging around. Then I cleaned off any dust/metal fragments.

Step 3: Install the Card

After this is just a matter of installing the card into the computer. You can do this with or without the main video card installed. This is really just like installing a standard video card. The only difference is that you should take extra precaution to make sure the card isn't in contact with anything metal. Remember that there will be very small points along the cut that could be live. If metal is sitting close to where you've cut the card then maybe place some electrical tape along the cut.

Now just hook up a monitor to this card and power on the computer. There is no need to install the other video card and no need to run 3 monitors just yet. If you get anything showing on the screen then it has worked. Now just shut off the computer, install the main video card and you're done.

Step 4: The Results

The end result is a computer that will run up to 4 monitors quite nicely. In my case I am running 3 monitors via DVI connections. I don't play games but I believe the 3rd monitor will be slower for games because the bandwidth between the motherboard and the card is reduced to 1/16th of it's original speed. This is still more than fast enough for windows though.

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    57 Comments

    0
    joearkay
    joearkay

    8 years ago on Step 4

    There is no way that would work :@

    0
    MikeKulls
    MikeKulls

    Reply 1 year ago

    I used this for years and it worked no problem. Only reason I don't use it now is new PC runs 3 screens as is.

    0
    MikeKulls
    MikeKulls

    Reply 8 years ago on Introduction

    I can understand your scepticism but this does work. I've done it with 3 different video cards and had it running for several months. If you install a 1x card in a 16x slot that works no problem because the motherboard knows not to use the other pins. The same is true in the reverse situation. The extra pins just add extra bandwidth.

    0
    joearkay
    joearkay

    Reply 8 years ago on Introduction

    Ok I take it back now that I understand the theory behind it

    0
    ImageMaker
    ImageMaker

    Reply 8 years ago on Step 4

    As long as you don't create a short between traces at the cut, this is electrically the same as plugging the card into an old full length PCIEX1, X2, or X4 slot in a five or six year old motherboard -- which works fine. Those older boards have the same connector as a modern PCX or PCIEX16, but most of the pins aren't connected -- and all PCI Express video cards are designed to be backward compatible to the earliest full length PCI Express slots. The extra pins (that are cut off in this instructable) provide a "wider" connection -- the original is 8 bits wide, while the X16 is at least 64 bits wide (same as the memory bus in the last few generations of motherboards).

    The card in the X1 slot will be a LOT slower than it would be in the proper X16 slot, but as noted, for email and Windows desktop, even web browsing that doesn't involve streaming video, that barely matters -- and if you run games, you just have to be sure to put the game window on a monitor connected to the card in the PCX/PCIEX16 slot.

    BTW, this will work a lot better if you have plenty of RAM in the computer...

    0
    nandoi2c
    nandoi2c

    3 years ago

    goood, what is the model of two videocards?

    0
    batvanio
    batvanio

    3 years ago

    And does the processor have an embedded video card? This will save the addition of a second one.

    0
    Gabse
    Gabse

    8 years ago on Introduction

    Oh thanks!!!!! I only have 2 questions:
    How can i put the taskbar over three monitors, and does it supports Nvidia SLI?

    Gabs'e

    0
    duceduc
    duceduc

    Reply 5 years ago on Introduction

    I just found out about DisplayFusion. I believe you can add taskbar to every monitors with this program.

    0
    TheParacorder
    TheParacorder

    Reply 8 years ago on Introduction

    in order to do SLI you need 2 IDENTICAL cards, otherwise further issues may occur

    0
    Blackice504
    Blackice504

    Reply 8 years ago on Introduction

    This is not SLI as both cards are been used for monitors in SLI one of the primary things that goes on is Both cards are been used for one monitor in terms or processing.
    keeping it very simple.
    this is dual video cards used for multiple montor support and this does work, how ever i do not think its wise to cut the PCI-E pins in this manner due to the fact you will have to be very carefull as you will have expossed pins, to avoid this use tape or some insulation especially where you have a board that has a pci-e in front of the a south bridge or other controller that has a heatsink that can short the card.
    Best option if you have the money, USB to DVI, its basically a video card on usb and with usb 3.0 i think we might even see one with 3D support.
    Or USB Monitors these montiors run directly from USB (including power)
    you can also buy a PCI or 1x PCI-E video card.
    PCI cards are very cheap second hand if your board has a PCI slot spare.
    Most Expesive option is to get a Video card that supports 3 or 4 monitors but the cost can be a little too much due to the fact the cards support 4 monitors and not much else (poor 3D performance).
    PS there is also Hybrid SLI never tested it but that allows you to have two different Nvidia GPU's, or you can have a Nvidia Card as Video and the other card set as PhysX card in this you can use 2 different cards. Research.....

    0
    TheParacorder
    TheParacorder

    Reply 8 years ago on Introduction

    I didnt say this is SLI. I said that is Gabse wanted to use SLI, he would need 2 of the same card, and the hybrid way around that, may become an issue

    0
    Blackice504
    Blackice504

    Reply 8 years ago on Introduction

    thats where your wrong again hybrid SLI or Crossfire has not been an issue for years.
    if your 13 why is your avatar of an older guy and looks like his wife?
    i started messing with computers when i was 6. "back in dos"
    if you have any problems or want to ask questions your welcome to contact me or this guy who made the Instructable as i agree with him he seems to know his stuff, well apart from the gigabyte heater lol.
    Oh here is one thing that many young people don't get or starting to learn Apple makes cheap Devices "as it has limited functions like a DVD player" a Computer does anything you want it to you just have to know how.
    also give ubuntu a try in live mode it is a good os and plenty of info to get it running.

    0
    TheParacorder
    TheParacorder

    Reply 8 years ago on Introduction

    Thats my father and me :/ i had very long hair at the time.. I am not new to electronics.. Im slightly new to PC building. I very much agree you have more knowledge than me. This is simply our age difference. I respect you. And i know the stuff i needed to know how to build a PC. Not much more. You are kind enough to help young with technology. But im less in need to be taught. And i am a PC loyalist. I have some knowledge of C++ and arduino programming. Im not a mindless little twerp who says "swag" "yolo" or any
    Junk like that. Im in fact the one to be picked on... So please support me.

    0
    Blackice504
    Blackice504

    Reply 8 years ago on Introduction

    could not see that detail of the pic until i enlarged it, i have an Arduino as well, not done to much with it other then use it as an invertor controller and L.E.D cube C++ is good to know but i think you should start learning Java as many programmes are writen in java, its good your a pc man. keep in touch and if you have any questions about stuff just message me and that goes to anyone else too. Talk to you later bro.

    0
    TheParacorder
    TheParacorder

    Reply 8 years ago on Introduction

    Yes, i am well aware of that. I wont be doing this instructable anyways. (My computer is custom built, and less than a year old) i was actually telling the comment above me how SLI works. My graphics card supports 4 screens. It costed only 300

    0
    Gabse
    Gabse

    Reply 8 years ago on Introduction

    Thanks for your answer. I have decided not to use sli (too expensive :-)) still have a question: what graphics card do you use?

    0
    TheParacorder
    TheParacorder

    Reply 8 years ago on Introduction

    No problem! And i currently run two amd radeon 6870's in sli :) i have a video on youtube. Look up FSstudios1 and my video will be under there. Take care
    -Evan