120Hz monitor usage

120Hz TVs and monitors don't actually run from 120Hz, they run at 120Hz. They have internal timing controllers and other circuitry that insert an extra frame between normal 60Hz rate frames. So the people at the store were not incorrect. The Mac won't prevent your monitor from doing it's 120Hz thing.

So are you wanting to run 3D? That wasn't clear.

While it's true that most 3D systems run at 120Hz, in order to do so, they halve the horizontal resolution. So in the case of a monitor or TV with 1920 x 1080 panel resolution, you get 960 x 1080 left eye perspective, and then 960 x 1080 right eye perspective each at 60 frames per second (fps) for a total rate of 120 fps. So they play tricks with resolution (halving it) in order to double the frame rate.

I am not totally familiar with the market segment you are talking about, but in order for your Asus to do true 1920 x 1080 at full resolution and 120Hz frame rate, that would require dual-link DVI. Does it have dual-link DVI? In that case you may be able to run it using the correct Apple adapter, namely this one:

http://store.apple.com/us/product/MB571Z/A

But depending on the EDID inside the display, you might also need to use SwitchResX in combination with the above adapter to get it to work.

I am in the exact same boat as you with my new Sony Vaio Z (uses 330M as well) and the same Asus VG236H LCD. I imagine if you were able to get 120hz working you would be able to get the 3D working...but really...I mostly just want the 120hz for 2D Gaming. I have tried hooking up via HDMI and DVI-D (using a Vaio Dock) to no avail.

Been playing around with different drivers for a bit, but haven't found the right one.

Anybody with Acer, Asus, or Samsung 120hz LCD get theirs to work with a notebook?

Boardshop and prog, neither of you have confirmed trying dual-link DVI. It's not enough that you are using a dual-link cable. You also need to ensure you are connected to a dual-link interface on the computer in question. It's a fact you won't get 120 Hz out of single link DVI, not without dropping the resolution a great deal.

Pushing two megapixels (1920 x 1080) out a port at 120 Hz has the same bandwidth requirement as pushing four megapixels (2560 x 1600) out a port at 60 Hz. In other words, it takes the same bandwidth and interface to drive the Asus as it does a 30" Cinema Display. In this case, both use dual-link DVI.

Have you perhaps tried driving the Asus at 1024 x 768 and 120 Hz? That should work over single link DVI. It might tell you if the OS is the limitation or not. It's not a sure test, but it's something to try in the absence of having dual-link running, which it sounds like neither of you have.

I guess I am not understanding the question.

No, sorry, it is I who have misunderstood. I didn't realize you had the dual-link Apple adapter. I somehow had assumed you were using the cheaper, single-link Apple Mini DisplayPort to DVI Adapter.

So in that case you have shown that Mac OS is possibly not savvy about 120Hz. I suppose the final step to take, assuming you want to try and take this further, would be to download SwitchResX and see if you can put it's features to use. One thing it can do is read a display's EDID. That would tell you if the Asus has a well formed EDID or not, meaning in this case that it is informing the Mac through EDID that it supports 120 Hz. It could be that is missing from the driver (EDID).

The other thing SRX can do is allow for the building of custom timings. You could try manually building a 120 Hz timing and see if it is accepted as valid by the Mac hardware and software and hopefully then the timing will become active and selectable within Displays Preferences.

Still working on the issue on my end.

Although I am using Windows on my Vaio, I would like to be able to hook a Macbook Pro up to the same monitor (I have the Dual Link DVI display port adapter)...but right now I'm more concerned with getting the Vaio working as that is my primary gaming laptop (want to bring the 120hz LCD + Vaio to lans).

No progress really yet so far....

BSteely - as far as I can tell, the laptop dock does do Dual Link (link: http://www.sonystyle.com/webapp/wcs/stores/servlet/ProductDisplay?catalogId=1055 1&storeId=10151&langId=-1&productId=8198552921666055167&tab=featuresTab#specific ations ), but I'm not 100% on that. The cable is definitely dual link, but as you pointed out, wont help if the dock doesn't support it.

Hooking the monitor up either way, DVI-D using the dock or HDMI direct from the Vaio Z, Windows 7 doesn't detect the monitor, it just comes up as Generic PNP Monitor. It appears as you may be right about it not getting the EDID as I did somewhere get something about it not getting the DDC info.

Anyway..I'll keep you posted and if I get it working Ill try getting the MBPro to work.