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I have two computer monitors, and I wanted to hook up my TV to my pc as well. I have my TV plugged into my pc (VGA), and I have a 2 Port VGA Video Splitter from StarTech for my two monitors.

All three are working, but two are duplicates. I guess it is a problem with my VGA Splitter. However if I just have two monitors plugged into the splitter, they work fine and I have two screens. So I am slightly confused. In devices it only detects Second Monitor, no third or anything ^^

Any thoughts? Anyone else running three monitors without problems?

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Your video card might not support that. I tried to connect three monitors to a laptop. Windows saw all three but it could use only two of them, unfortunately. – Alexey Ivanov Oct 30 '12 at 18:53
what kind of video adapter is it? What exact "splitter" are you using? Are all three monitors using VGA connecitons? – Ƭᴇcʜιᴇ007 Oct 30 '12 at 18:56
@techie007 Probably a DMS-59. It was common on Dell's, maybe other OEMs. – Louis Oct 30 '12 at 19:23
@techie007 It is a 2 Port VGA Video Splitter from StarTech, product code: St122LE – Hazza Oct 30 '12 at 19:42
up vote 2 down vote accepted

It depends on your graphics card.

Windows has supported more than two monitors since Windows 98. You just needed the hardware support to enable this.

If you have an AMD card, you need an Eyefinity-enabled card, that has DVI and DisplayPort/mini-DisplayPort outputs. Cards of the Radeon HD 5000 generation and later will work. You'll have to have at least one of the monitors plugged into the mini-DisplayPort/DisplayPort output to a DisplayPort-enabled monitor. Or, if you only have DVI inputs, you'll need an active (mini) DisplayPort to DVI adapter.

If you have nVidia, you need two cards in SLI to drive three monitors using their 3D Vision technology.

You can also do this with multiple graphics cards installed. This is how you did it back in the Windows 98 days. However, in this configuration, you won't be able to game or use hardware video processing on using all of them. But for basic work, it works fine.

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I was afraid my hardware might not support it. I was trying to be sneaky using the splitter to get more screens but I guess it doesn't quite work like that :P I'm bad. My PC is quite old and I only have 1 graphics card. I have a ati radeon HD 4870 I think. I actually just noticed (rather stupidly) that it has a HDMI input as well as VGA and DVI. If I was to connect my TV via HDMI, one monitor through VGA and one via DVI, might I have more luck? Thanks for your reply btw – Hazza Oct 30 '12 at 19:52
The HDMI and DVI outputs both share the same display out, so unfortunately that won't be possible. – Ben Richards Oct 30 '12 at 20:07
Ah ok, thanks a lot for your help. Guess I will just do a lot of reaching around my pc to plug in the hdmi ^^ I'd vote you up but I appear to have a lack of reputation. I won't forget! – Hazza Oct 30 '12 at 21:42

I use a DisplayLink adapter. It plugs into my USB ports and then powers a monitors. In fact, for my laptop, I have three monitors PLUS my laptop display (that makes four!). Output is DVI on most devices.

You might need a USB hub (one USB port per monitor) but this is SO MUCH cheaper than super graphics cards. My desktop has a super graphics card but it cost me a fortune and a new power supply, too!

Honestly, I haven't figured out why these are way more popular. Performance is great, by the way, just not for full screen gaming.

Mine look like this: enter image description here

Here's a list of supported devices, too

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Yeah that looks pretty cool, fairly expensive, not sure I can afford such a device. But still sweet, cheers :) – Hazza Oct 30 '12 at 21:46

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