MP 1,1-5,1 7950 mohave triple monitor

[aawong]

I just installed a radeon 7950 not Mac efi. The card has Two dvi, one hdmi, one dp
I have three 23" cinema displays.
Two in the dvi and one in the dp but only two monitors works.
Do I need to have one in dvi, one in hdmi, and one in dp to work?
Do any of the adapters have to be active?

 

[joevt]

You did not say which monitors work. Try one monitor at a time. Test each port individually. Get a passive HDMI to DVI adapter.

 

[aawong]

You did not say which monitors work. Try one monitor at a time. Test each port individually. Get a passive HDMI to DVI adapter.

Hi I have tried every combo all ports work just with two monitors not three. I read somewhere the third port needs to be acti e

 

[joevt]

I guess you need an active DP to DVI adapter, or an active DP to HDMI adapter with a passive HDMI to DVI adapter.

 

[aawong]

Does the active adapter need to be dp or can it be hdmi instead?

 

[joevt]

Does the active adapter need to be dp or can it be hdmi instead?

I don't know. You are trying to connect 3 DVI displays. HDMI is the same as DVI so there's no active adapter.

DisplayPort can output DisplayPort or HDMI. HDMI comes from DisplayPort Dual Mode functionality (DP++) which uses a passive adapter to voltage-shift the HDMI bits from the DisplayPort port to the HDMI/DVI side (since DisplayPort and HDMI/DVI use different voltages). The requirement for an active adapter might be because the card can't do three HDMI/DVI type adapters (TMDS clock limit? - I don't know). An active adapter takes a DisplayPort signal (not using DP++) and converts it to DIV/HDMI.

DisplayPort Dual Mode (DP++) is usually limited to HDMI 1.4 (twice the bandwidth of DVI). An active adapter can output HDMI 2.0 (nearly four times the bandwidth of DVI).

Anyway, if it's possible to connect 3 displays, and an active adapter is required, then this is the only option you haven't tried yet.