1080p 120hz

[MrDowntempo]

I have a 120hz 1080p television. Is it possible to force 120hz out of my 4870 instead of what appears to be the max my card supports for 1920x1080 which is 60hz?

I may be upgrading to crossfire down the line too. I have a friend with the same card as me, but who plans on upgrading when the 4900 series comes out and I may get his old 512mb 4870 for cheap. With 2 cards in crossfire would it be possible to push the 120hz?

Thanks in advance,
MrDowntempo

 

[Mindoculus]

this is a hardware limitation issue . . . the vast majority of LCD monitors
do not render faster than 60mhz.

video cards work with frames per second that may far exceed a television or
monitors 120mhz but your LCD monitor mhz is capped at 60. CRTs, if you
have one, have higher refresh rates.

i think the one or two exceptions were unveiled this year and i don't know if
they are on the market yet.

 

[MrDowntempo]

Actually 120hz is getting to be fairly common. There were one or two 240hz televisions unveiled this year.

 

[Nenu]

You will need a HDMI gfx card get 120Hz at 1080p unless the TV has Dual DVI in.
Dual DVI cards wont work because there is no converter to get dual DVI down HDMI, only single.

 

[MrDowntempo]

So a DVI port is not powerful enough, or doesn't have enough bandwidth for 120hz? My GPU is a 4870 that has dual DVI and I have the included DVI to HDMI adapter. THe motherboard has a 790gx chipset with onboard video with a true hdmi port. Could I use that and still have the 4870 do all the work? Maybe Hybrid Crossfire or something?

 

[criccio]

You people and you're "higher number = better" idea...

I would be perfectly happy with a 24Hz LCD for movies at least. All you need. Regular PC usage that wouldn't be the case.

 

[Nenu]

So a DVI port is not powerful enough, or doesn't have enough bandwidth for 120hz? My GPU is a 4870 that has dual DVI and I have the included DVI to HDMI adapter. THe motherboard has a 790gx chipset with onboard video with a true hdmi port. Could I use that and still have the 4870 do all the work? Maybe Hybrid Crossfire or something?

Not enough bandwidth on single DVI (HDMI conversion) for 120Hz at 1920 res, no matter how you connect it.

 

[evilsofa]

I have a 120hz 1080p television. Is it possible to force 120hz out of my 4870 instead of what appears to be the max my card supports for 1920x1080 which is 60hz?

No, because it's not possible to force your television to take 120Hz.

120Hz (and 240Hz, and 480Hz) LCD TVs are faking it. What really happens is that they take a signal of 60Hz or less and insert frames to make a smoother picture.

Here's why: film is recorded at 24 FPS and video is recorded at 30 FPS. When you show video on a 60Hz LCD TV, it looks great because the TV just shows every frame twice. But when you show 24 FPS film on a 60Hz LCD TV, it doesn't look right because it has to drop every third frame (film buffs have been complaining about this). The first number that both 24 and 30 divides evenly into is 120.

So here's what your 120Hz LCD TV does: when it gets a 24 FPS source, it inserts 4 duplicate frames between each original frame, and when it gets a 30 FPS source, it inserts 3 duplicate frames between each original frame. More advanced TVs interpolate the duplicate frames to make an even smoother image. This will not - and can not - help gaming at all, and in practice all 120Hz LCD TVs have been found to have a lot of input lag.

Under no circumstances will these 120Hz TVs take more than 60Hz from the source. There are, at the time of this writing, exactly two 120Hz LCD monitors that will actually take 120Hz from the source - the Samsung 2233RZ and the Viewsonic VX2265WM. If it is not one of those two monitors, you will not be able to display true 120Hz.

As others have noted, a single DVI port doesn't have enough bandwidth to show 1920x1080 at 120Hz.

 

[JohnleMVP]

+1 evilsoft is correct, your TV really isn't 120Hz.

Its reusing frames so the motion seems smoother to your eyes.

 

[niceguy1234]

I have a 120Hz Toshiba 46" LCD TV. When I choose 120Hz in CCC, it accept the setting. But the pointer is lagging like crazy. So I set it back to 60Hz. I have no problem watching Blu-ray movie using 60Hz setting. The movie plays very smooth in my eyes.

 

[criccio]

I have a 120Hz Toshiba 46" LCD TV. When I choose 120Hz in CCC, it accept the setting. But the pointer is lagging like crazy. So I set it back to 60Hz. I have no problem watching Blu-ray movie using 60Hz setting. The movie plays very smooth in my eyes.

23.976 and 24 are not multiple's of 60 so that is impossible. What is the exact model number of you're TV? Does it accept a 1080p24 signal?

 

[bfellow]

No, because it's not possible to force your television to take 120Hz.

120Hz (and 240Hz, and 480Hz) LCD TVs are faking it. What really happens is that they take a signal of 60Hz or less and insert frames to make a smoother picture.

Here's why: film is recorded at 24 FPS and video is recorded at 30 FPS. When you show video on a 60Hz LCD TV, it looks great because the TV just shows every frame twice. But when you show 24 FPS film on a 60Hz LCD TV, it doesn't look right because it has to drop every third frame (film buffs have been complaining about this). The first number that both 24 and 30 divides evenly into is 120.

So here's what your 120Hz LCD TV does: when it gets a 24 FPS source, it inserts 4 duplicate frames between each original frame, and when it gets a 30 FPS source, it inserts 3 duplicate frames between each original frame. More advanced TVs interpolate the duplicate frames to make an even smoother image. This will not - and can not - help gaming at all, and in practice all 120Hz LCD TVs have been found to have a lot of input lag.

Under no circumstances will these 120Hz TVs take more than 60Hz from the source. There are, at the time of this writing, exactly two 120Hz LCD monitors that will actually take 120Hz from the source - the Samsung 2233RZ and the Viewsonic VX2265WM. If it is not one of those two monitors, you will not be able to display true 120Hz.

As others have noted, a single DVI port doesn't have enough bandwidth to show 1920x1080 at 120Hz.

120HZ and 240Hz are best for 24fps sources though and best for films.