Adding second or more monitors to old 2008 IMAC

[Luke Klink]

Hi,
I have a 2008 IMAC with El Capitan and 4GB RAM.

How would I go about adding a second or even a third monitor (bigscreen TV) to this computer? Nothing huge, just need a bigger screen that my older eyes can see while working. I think the screen on the computer is 20 inches. So maybe I would like to add a 32-inch monitor and maybe a second?

Is it possible to run all the screens then and drag/drop between them once up and running?

Thanks so much for your help. I found this forum totally helpful earlier this year with updating my OS and RAM.

Thanks again.

Luke

 

[Cory Cooper]

Hello,

Your Early 2008 iMac has a single Mini-DVI display port, so it only supports a single external monitor. A couple of adapters that may work for you:

VGA
VIMVIP Mini DVI to VGA Adapter Cable for Macbook White

HDMI
StarTech.com Mini DVI to HDMI Video Adapter for Macbooks and iMacs- M/F - MacBook Mini DVI Adapter - Mini DVI to HDMI Cable

Hope that helps,

C

 

[Luke Klink]

Hi Cory.
Thanks for your help on this. I am going to give it a try, connecting a 32-inch monitor to my imac. Do you know if my imac screen will still keep working while using the larger external monitor (maybe as a drag-drop clipboard type of function)? I was going to connect a couple of smaller monitors, but since only one will work I am going to try the larger 32-inch monitor. My 20-inch imac screen is kind of small for my aging eyes and multiple programs I keep open.
I assume the HDMI is the best option.
Thanks so much for your help.

 

[Cory Cooper]

Hello,

Yes, both the internal and external will work simultaneously. You can use them as separate display spaces/extended desktop, or in a mirrored configuration, which shows the same on both.

Yes, the Mini DVI to HDMI would be the best way to go, although you won't get audio through the 32".

C

 

[Luke Klink]

Thanks for the advice.

I have the TV and Mini DVI to HDMI all connected, and the iMac seems to be detecting the connected TV, but I can't get anything to display other than "No Signal" on the TV. I tried both HDMI ports on the TV. Any thoughts?
I'll attach a screenshot that seems to show the TV is being detected.

 

[Lufbrarunner]

Have you set the 'Source' on your TV?

 

[Luke Klink]

Yes. I tried both inputs HDMI 1 & 2.

 

[Luke Klink]

I found this on the MAC website, although this is for a late 2009 imac and mine was purchased in 2008. Could it be that my 2008 imac won't support my new 32-inch TV? This is the first I heard of a size limit for the TV... (see last line below)


Graphics and video support

• 
  
• Mini DisplayPort output port with support for DVI, VGA, and dual-link DVI via adapter4
• Built-in iSight camera
• Support for extended desktop and video mirroring modes
• Simultaneously supports full native resolution on the built-in display and up to a 30-inch display (2560 by 1600 pixels) on an external display

 

[Luke Klink]

The 32-inch VIZIO TV I bought doesn't work on my work IMAC, but it works perfectly on my home DELL computer.
My 27-inch home DELL computer monitor works on my work IMAC without any problems

At work, the VIZIO screen never blinks or anything when connected to the IMAC, so for whatever reason there appears to be no signalk going from the IMAC to the VIZIO. The IMAC is showing the VIZIO is connected.

 

[Cory Cooper]

Hi,

Sorry for the delayed reponse - life got in the way.

I haven't heard of that limitation either. I would think any limitation would be resolution, not screen size. Depending on the model of the VIZIO, if it is a 1080p TV, it would have a resolution of 1920x1080. That easily fits within the iMac's capabilities, and is under the 2560x1600 resolution of the old 30-inch Apple Cinema Display's 2360x1600 resolution, which is what I gather that spec is referring to.

What model is the VISIO?

C

 

[Luke Klink]

Hi Cory,
Thanks for offering to help.
The model is Vizio 32 class smartcast FHD (1080p) Smart Full Array LED TV d32f-f1)
The Imac shows D32F-F1 as being connected, so that must be the model number.
The VISIO works fine on my home PC, and my home PC monitor works fine with the IMAC at work.
When I connect the VISIO to the work IMAc though, the screen just shows a steady screen image for both HDMI ports 1&2 I try. It looks for whatever reason there is no signal getting from the IMAC to the VISIO.
Thanks again for your help. I really like being able to work with the second screen now that I have my DELL monitor from home hooked up, but I'd really .like to get this new TV running with the IMAC.

 

[Luke Klink]

HEY!!! I ordered a different company's mini DVI to HDMI adapter and the VISIO started right up with my IMAC! Weird the first adapter would work with the DELL monitor but not the VISIO.

Anyway... AWESOME!!!

I can't tell you how helpful you have been through all this, and how much I totally appreciate your assistance. Now I don't have to squint to see work on my 20-inch IMAC screen (or unpile windows piled on top of other windows) , and the second screen gives me even more workspace.

LOVE IT!!

 

[Cory Cooper]

Hi,

I was just typing a response that it may be the adapter. Glad it is working finally!

No need to thank me, that's why we're here.

Be well and enjoy,

C

 

[KimyLawkins]

Hello,

Your Early 2008 iMac has a single Mini-DVI display port, so it only supports a single external monitor. A couple of adapters that may work for you:

VGA
VIMVIP Mini DVI to VGA Adapter Cable for Macbook White

HDMI
StarTech.com Mini DVI to HDMI Video Adapter for Macbooks and iMacs- M/F - MacBook Mini DVI Adapter - Mini DVI to HDMI Cable

Hope that helps,

C

I am so happy to see my exact question asked by someone else. I have a similar situation a 2008 Imac I use for working at home same, memory and it works great but I need to add a monitor. I figured for now I would just add my 13" macbook pro (2021) I ordered an adaptor "Mini Display Port Adapter Cable and plugged it in and NOTHING. I am bummed. I think I may order the one you mentioned to Luke Clink and see if it makes a difference. If you have any suggestions I would love to hear them.
Kim Lawkins

 

[Cory Cooper]

Hello and welcome.

Unfortunately, you cannot connect your iMac and MacBook Pro together to use as a second display. You can purchase an adapter to connect an external to wither the iMac or the MBP, but they have different connectors and would use a totally different adapter. You would also need to purchase/use an external display or TV.

Hope that helps,

C