PDA

View Full Version : G74sx and ASUS VG278 monitor - 3d query



An-0_0-bis
08-07-2012, 05:05 PM
Hey all,

I'm currently in the market for a 3d monitor, preferably the ASUS VG278 which has Lightboost and Nvidia 3d vision 2 (glasses inclusive).

After doing HEAPS of reading on the internet, I'm still unsure as to what refresh rates I can achieve if I hook this monitor up via HDMI.

I've read that if I use the laptop at 1080p with HDMI, the refresh rate on the monitor will only be 60hz, however it will be 120hz at 720p. Is this true?

My issue also is - What would the refresh rate be if I am to run the laptop at 720p, via HDMI, with 3d viewing/gaming enabled? Would the refresh rate be 60hz or 120hz in this resolution? I understand that 720p 3d @ 60hz would be fine, as the framerate would probably not peak over 60 anyway during 3d gaming on the g74sx.

Thanks, Rob

xeromist
08-07-2012, 05:20 PM
You can only get 120Hz at 720p. Higher res will have a lower refresh as you noted. And whatever the refresh is for a given resolution, it will be half per eye in 3D mode. FWIW, virtually all 3DTV has the exact same limitations due to HDMI speed. Also, consider that 3D mode makes the GPU work harder for the same effective frame rate. Given mobile GPUs being weaker than their desktop relatives it might not be a bad idea to run in 720p.

An-0_0-bis
08-07-2012, 05:40 PM
Thanks for the reply, that's exactly what I was thinking, the framerate in 3d mode will definitely drop.

To be completely honest, I'm not overly fussed about running games in 720p with OR without 3d enabled. Currently bf3 is running at an avg of 80-90fps with most settings on Medium in 1280x720, and the game still looks amazing. I was very concerned with what the framerate would be like while watching 3d movies off my ps3 on the monitor, but if it will run 3d 720p @ 60hz then that would be fine. Surely the HDMI lead wouldn't create any extra input lag while pc gaming?

It really is a shame the G74sx didn't come with a dual-link dvi port...

xeromist
08-07-2012, 08:08 PM
I think the assumption was that as a mobile device it would be used more often with televisions and those all have HDMI. Not to mention HDMI carries audio so that simplifies connections.

As to input lag, the HDMI packaging process is quick so that shouldn't cause much. Most input lag results from pre-processing inside of televisions. If you are using a PC monitor most of those have minimal processing and some even have settings to further speed up the refresh rate(like gaming modes).

On a side note: The latest HDMI standard can support 1080p @120Hz but most of the processing chips aren't capable. There are a few chips on a handful of the newest high end hardware that can do it but it will be a while before it is widely compatible on most sources & displays. That is to say it won't help you on your current conundrum but perhaps by the time you are ready to upgrade your machine you will get a proper full res 3D mode.

Shawnnepc
08-07-2012, 11:01 PM
I think the assumption was that as a mobile device it would be used more often with televisions and those all have HDMI. Not to mention HDMI carries audio so that simplifies connections.

As to input lag, the HDMI packaging process is quick so that shouldn't cause much. Most input lag results from pre-processing inside of televisions. If you are using a PC monitor most of those have minimal processing and some even have settings to further speed up the refresh rate(like gaming modes).

On a side note: The latest HDMI standard can support 1080p @120Hz but most of the processing chips aren't capable. There are a few chips on a handful of the newest high end hardware that can do it but it will be a while before it is widely compatible on most sources & displays. That is to say it won't help you on your current conundrum but perhaps by the time you are ready to upgrade your machine you will get a proper full res 3D mode.

You'd need a HDMI 1.4a port to output 120Hz.

The G74 is only HDMI 1.3 :)

xeromist
08-08-2012, 02:50 PM
You'd need a HDMI 1.4a port to output 120Hz.

The G74 is only HDMI 1.3 :)

Yes, that's my point. This machine won't do it but his next machine might. That's what I meant by "upgrade", as in "upgrade to something else". :)