5850 - hdmi, refresh rate and overscan woes

[Mistral]

Just got a 5850 and as awesome of a video card it is, there are some annoying problems that from what I understand plague quite a few users.

HDMI connection to a TV (Toshi 525 in my case)...

First, I went through all the hoops to solve the overscan problem caused by the driver's default settings. Here's the next roadblock: the card decides to output some games at 30Hz instead of the usual 60Hz that it should use at 1080p. This I quite notice since I usually have v-sinc on too.

Is there a way to force the card to keep the refresh rate at 60Hz?

 

[air_ii]

Destkops & Displays -> Click on the white "triangle" of the display you want to change and then properties.

Unless you mean that it's set to 60Hz but all of a sudden it changes to 30? I haven't seen that behavious on my card...

 

[Mistral]

Unless you mean that it's set to 60Hz but all of a sudden it changes to 30? I haven't seen that behavious on my card...

Aye...

Toshi 525, 1080p, Fraps + v-sinc...
NFS Shift, Red Faction Guerrilla... all good, 60Hz.
Juiced 2... wham 30 frames...
Armoured Princess... wham 24 fps...
The Heaven bench... never breaks 30... however, if I swap to DX10, it goes up to 60 in some scenes...

In any case, got the W7 upgrade disk sitting here, I'll give that a try later today and report back....

 

[air_ii]

Aye...

Toshi 525, 1080p, Fraps + v-sinc...
NFS Shift, Red Faction Guerrilla... all good, 60Hz.
Juiced 2... wham 30 frames...
Armoured Princess... wham 24 fps...
The Heaven bench... never breaks 30... however, if I swap to DX10, it goes up to 60 in some scenes...

In any case, got the W7 upgrade disk sitting here, I'll give that a try later today and report back....

Turn off vsync, everything should be fine. It's not refresh rate problem, it's how these games/programs respond to vsync. I'm guessing Juiced 2 (for example) locks the refresh rate at divisibles of 60. So when your card can't maintain 60 fps, it lowers the framerate to 30 to sync it with your displays vertical refresh rate and avoid stuttering at the same time...

 

[Sasqui]

Turn off vsync, everything should be fine. It's not refresh rate problem, it's how these games/programs respond to vsync. I'm guessing Juiced 2 (for example) locks the refresh rate at divisibles of 60. So when your card can't maintain 60 fps, it lowers the framerate to 30 to sync it with your displays vertical refresh rate and avoid stuttering at the same time...

That's interesting, haven't seen an application that forced Vsync.

One thing I noticed in Dirt2 and Half Life - enabling Vsync really made things smoother. Screen tearing completely gone and no lags or stuttering. If it is indeed pumping out a clean 30 fps, it's plenty good for my human eye.

 

[erocker]

Aye...

Toshi 525, 1080p, Fraps + v-sinc...
NFS Shift, Red Faction Guerrilla... all good, 60Hz.
Juiced 2... wham 30 frames...
Armoured Princess... wham 24 fps...
The Heaven bench... never breaks 30... however, if I swap to DX10, it goes up to 60 in some scenes...

In any case, got the W7 upgrade disk sitting here, I'll give that a try later today and report back....

If you are using Fraps, it always will cut down your framerates. I would suggest setting everything to default in CCC and use application settings. Most games/applications have V-sync settings. You are most likely just doubling it up by using V-sync in CCC.

 

[SummerDays]

That's interesting, haven't seen an application that forced Vsync.

One thing I noticed in Dirt2 and Half Life - enabling Vsync really made things smoother. Screen tearing completely gone and no lags or stuttering. If it is indeed pumping out a clean 30 fps, it's plenty good for my human eye.

I'm just laughing here, because, Vsynch is one of those poorly understood options.

 

[Sasqui]

I'm just laughing here, because, Vsynch is one of those poorly understood options.

Don't know a heck of a lot myself. Question is, when it's on, what determines how many frames per second can be rendered. The graphic card has to figure... and wait for the exact moment to push a full frame to the display. There has to be a lot going on there.

 

[Steevo]

I'm just laughing here, because, Vsynch is one of those poorly understood options.

Great that you are laughing.

Most useful post.

 

[air_ii]

If you are using Fraps, it always will cut down your framerates. I would suggest setting everything to default in CCC and use application settings. Most games/applications have V-sync settings. You are most likely just doubling it up by using V-sync in CCC.

From my experience, it's not FRAPS, it's the game that cuts down the framerate itself. Here's why:

A game engine needs to anticipate, which frame to render next (as in how to set up the scene). Assuming a card is capable of rendering the scene at 19 fps, each frame is rendered for 52,6 milliseconds. Throughout this time, the screen has gone through 3,16 refresh cycles. Since the game/card needs to wait for the beginning of the next cycle to refresh the screen (vsync enabled), the frame is effectively rendered 66,7 milliseconds, which corresponds to 15 fps (assuming 60Hz refresh rate).

 

[Mistral]

A game engine needs to anticipate, which frame to render next (as in how to set up the scene). Assuming a card is capable of rendering the scene at 19 fps, each frame is rendered for 52,6 milliseconds. Throughout this time, the screen has gone through 3,16 refresh cycles. Since the game/card needs to wait for the beginning of the next cycle to refresh the screen (vsync enabled), the frame is effectively rendered 66,7 milliseconds, which corresponds to 15 fps (assuming 60Hz refresh rate).

This is absolutely true and quite visibly illustrated by the Heaven bench and the Unigine engine - turning on v-sync there results in the frame rate jumping between 60, 30, 20 an 15.

My problem was the 5850 actually changing the output modes between desktop and games, be it 60Hz, 30Hz or 24Hz. I say was, since upgrading to W7 seems to have solved it. Then again, it could've been just a driver snafu with ViSHTA.

The only weird thing left is Juiced 2, but I'm starting to think the game itself it locked at 30 fps, v-sync or not.