My computer has a DVI connection from it to the monitor. I'd like to run a
TV screen from it at the same time. There are splitter leads on Ebay that
are DVI in, and DVI and HDMI out. Which would give the connections I need.
But will it work ok? On a resolution which is within the capabilities of
an HD TV?
Active DVI DAs seem to be pretty expensive. But I'm only interested in the
Dave Plowman firstname.lastname@example.org London SW
Only if you're lucky.
The PC queries the screen on a DVI port to read the EDID information
(supported resolutions, colour depths and refresh rates etc) if both
screens are plugged in the PC will "hear" scrambled replies.
If you unplugged one screen while the PC booted, then plugged the other
in, provided the 2nd screen supported the resolution the PC had chosen
to use with the 1st screen, it might work, but I doubt the TMDS links
really expect to be split in such a way, and being terminated twice
could set up reflections of the signal, but if it happens to work
without too many sparklies ...
That's nice for you. I've never pissed around with cheap graphics cards,
so I have no reason to doubt you. I've seen plenty of dual-output PCs,
Equally, you have no reason to doubt me when I say that I have seen and
worked with plenty of PCs where the onboard graphics are DVI only, and
I've seen and worked with plenty of upgrade graphics cards that are DVI
only. Sometimes you get an adapter dongle, but not always.
Adrian! Just found this snippet from a PC link, which supports my claim
that most cards will run dual monitors:
"Maina Njuguna asked me what's required for a new desktop to run two
"First, you need two monitors.
You'll also need a graphics card that supports two monitors. It's a
pretty standard feature, these days. In fact, you'd probably have a hard
time finding a new graphics card that doesn't. Even graphics integrated
into a new motherboard will likely offer this support. You can easily
check the back of your PC to see how many monitor connectors it has."
*And this was 2 years ago*.
But it is from PCWorld.
I know I use a number of machines where number of active monitors
supported is less than number of available connections (one example is
laptops with HDMI and VGA that do not allow 3 screens). I think Dual
screen support is more more common than it used to be though.
Indeed and if they don't support using 2 connections, quite often a
cheap splitter adaptor will suffice, assuming that the system will
As for the article from PC World, many other sites agree with PC World's
statement. Even my 4 year old laptop runs 2 monitors using 1 HDMI and 1
There's nothing new about running two or more monitors. Macs you could
buy in 1987 could do it. For the last five years or so before I retired
in 2008, I was running a MacPro with three dual-port video cards, to
which five displays were attached. I used two for development and three
for network monitoring.
"The idea that Bill Gates has appeared like a knight in shining armour to
lead all customers out of a mire of technological chaos neatly ignores
The last three PCs I built used pretty bog standard Intel motherboards,
and to get the (other) specs I wanted I had to get boards with no VGA
(just DVI and DisplayPort). In two cases I had to buy cheap VGA cards so
that I could use the existing KVMs.
Use the BIG mirror service in the UK: http://www.mirrorservice.org
My posts (including this one) are my copyright and if @diy_forums on
That is, or should be, a software matter, nothing to do with the ports
in use. If the OS supports it you can either have an extended desktop
or do mirroring (same stuff visible on each display). You might use the
latter for teaching, one screen on your desk the other being a
Depends on OS support.
"That excessive bail ought not to be required, nor excessive fines imposed,
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