DC7900 GT610 issue.

[Bikerbob]

Hello all.

I am having a problem with my system when trying to use a DVI to VGA adaptor.

Build is EL Cap. and if I use the cable DVI direct to a monitor that can take DVI.. works like a charm. The adaptor I am using is a DVI-A analog adaptor.

If I use this adaptor on a PC.. works like a charm.. SO I assume this is something in the way EL CAP is playing with the PC hardware?

Any idea? I have tried this on another VGA monitor same issue. I am thinking maybe I need a specific DVI to VGA adaptor???

Thanks

James

p.s ok a little more testing.. I think this must be an OS issue. Same adaptor on one of the same monitors.. from a PC using a GT730 - so same vintage of card.. Something in the signal when El Cap screen comes up must change that is not the same as a PC???

 

[Bikerbob]

OK, doing a little reading. The connector on the GT610 and the GT730 are DVI - so they should support both digital and analog signals. The PC must be putting out both? or it sees the pins and sends either a Digital or Analog depending on the connection.

THE Hackintosh must have some graphic setting that I need to change because I think what is happening is.. Clover is loading and being seen because it is a hardware analog signal. but when the OS layer get involved it must be putting out only a digital signal because I guess the driver is saying to only send digital? If this sounds right.. what do I change???

James

 

[Adrian B]

Apple hasn't supported a 15 pin d-sub socket on any hardware that was built with Intel CPUs. The last Apple supporting the socket was the Mac Mini with the PowerPC chip-set. This model was introduced back in 2005;
https://everymac.com/systems/apple/mac_mini/specs/mac_mini_g4_1.42.html

From Snow Leopard onward many folk have often had issues with some combinations of video card and monitor using VGA (15 pin d-sub) and versions of OSX and later macOS.

Newer versions of macOS are more likely to work on cards that have a DisplayPort connection (none of the cheaper cards use this as it is mainly used for 4K resolution monitors), you also need an 'Active' DisplayPort to VGA connector. The passive models can not work. You might have luck with an active HDMI > VGA or DVI > VGA connection.

I wouldn't however recommend getting comfortable running a second monitor with a VGA connection in 2018 while using macOS. You would be better with a monitor that supports digital connections.

 

[Bikerbob]

thanks for the response Adrian B, so you are saying that it is not outputting Analog signals at all.. and MAYBE an active converter might work. This is all because of a desk and KVM setup I am trying to do with multi computers.. most of the others are older, and work on the VGA no issues.. but I will look into an active converter.. OR the Hackintosh has to go on the other desk with other stuff and a more modern monitor that can do DVI.

Thanks

James

 

[Adrian B]

An active adaptor *might* work, but I cannot guarantee that it will work or for how long. As a solution it is the cheapest thing that has a chance of working, the best option will always be a digital input on your monitor.

You are correct in your assessment that macOS is written to support lower power digital connections. A DisplayPort is the one that actually will work best at this and Apple do make DisplayPort > VGA for Apple users that need to use an older legacy VGA port on a projector. Active DVI and HDMI v1.4 adaptors have also has reasonable success, but I understand that macOS does see these connections differently and this *may* lead to compatibility issues in the future.

 

[Bikerbob]

Well this is an old build - I cannot go past El Cap with the GT610 - so if I can get this to work. Found one for $14. then I will go with it. If not I will use the digital monitor I have been using.. and setup the computer in a different spot. This is just a fun hobby machine.