SLI Update ?

Archives Forums/Blitz3D Bug Reports/SLI Update ?

RGR(Posted 2005) [#1]
Hello Mark Sibly
I switched to a new computer (see specs below) and noticed that only 2 or 3 of all Fullscreen Blitz3D Programs I have written or have downloaded as Demos do not run proper anymore.
If I change in settings of GeForce 7800 from automatic detection to SingleGPU then the programs seem to work normal.
When I compile them as Windowed they run normal as well.

It is hard to explain but I try to describe what I see:
Cameras get mixed completely wrong, if you have a normal 3D-Szene and have a SingleSurface System for displaying Text and HUD etc... Vertical Mouse Position changes Graphic Card 1 Memory to Graphic Card 2 Memory and shows its contents linewise...
CameraZoom does make the picture on Screen bigger or smaller but does not zoom depending in which Card Buffer it is displayed.
Flip True or False are not changing the following action:
Starting a fullscreen program it starts displaying the upper half rendered and lower half black and reveals part of the rest at a speed of about 5 lines per second. Showing a graphic (for instance a mousepointer) and moving the mouse you can make the picture complete while moving the mouse to the bottom of the screen.
But still the lower 100 lines are only changed when there is the mousepointer and Flip does not work for the lower 100 lines at all... there is only one graphic or object rendered over the other leaving the former contents as it is...


RGR(Posted 2005) [#2]
Problem is solved with new NVidia Drivers
Version 81.84 produces presumed "bug"
Version 81.85 Fullscreen Mode is back to normal (CORRECTION: see below!!!)

Edited on 2005/11/30
I forgot to tell that the Problem still exists ... I didn't switch SLI-Mode on ... so I thought Fullscreen Mode was back to normal ... it isn't

Mustang(Posted 2005) [#3]
As usual...

Genexi2(Posted 2005) [#4]
Now if only they'd get back to fixing the other graphical bugs they introduced in the 80.XX series....

Hotcakes(Posted 2005) [#5]
And the 7x.xx, 6x.xx and 5x.xx series'sss too =]

RGR(Posted 2005) [#6]
I forgot to report ... SLI Mode is still not working with Blitz3D in Fullscreen Mode

... and I have the feeling its the developers turn to get in touch with NVidia ... not mine

They fixed Quake 4 errors and several other things in the new driver 81.95 and I am somehow convinced that it were not the users that got in touch with NVidia...

Setting the GPU Rendering Mode from Automatic to Alternate Frame Rendering fixes it for Blitz3D ... but that's the same as if you disable SLI ... it is not a satisfying solution as long as I don't know the effects that has on other applications and games

Gabriel(Posted 2005) [#7]
All of my B3d games appear not to work on SLI-equipped systems. I'd really like someone to take this bug seriously and - if it is a driver bug - speak to Nvidia about it and get it sorted please.

RGR(Posted 2006) [#8]
Just to get this Problem on the main page again!
As more people use SLI ... as less can use Blitz Programs in Fullscreen Mode without that annoying switching to Single GPU by hand before running a Blitz Program and switching back to Multi GPU or Automatic detection in the NVidia Settings afterwards...

Robert Cummings(Posted 2006) [#9]
it is often up to games developers to make nvidia aware of the bug unfortunately...

RGR(Posted 2006) [#10]
That's why I thought this is the right place ... Game developers or in this special case: Game Engine developers like BRL ... we have not much influence ... it seems to be a Blitz DX7 issue.
All other development tools that were updated or switched to DX9 do not show that problem (Pure Basic, Dark Basic Pro).

It appears only in fullscreen mode and the second GPU reacts on the mouse position .. hard to decribe ... and screenshots are not possible because they show no error.
The screen is updated while flipped till the vertical mouse position. Mouse at the bottom ... full screen is updated ... mouse somewhere in the middle then flip works only till that position ... the rest is written over and over.

I would blame it on the way Blitz handles the double buffering ... other development systems do not have the problem... so the first try should be ... work on Blitz ... if this does not help then look for other possibilities...

After 5 month when I reported this the first time, there could have been done something, if BRL would care about their flagship (quote Blitzbasic homepage: Our flagship product is Blitz3D,...) instead of letting it get rusty

Ross C(Posted 2006) [#11]
This sounds like it could be quite a crippling bug as time goes on if not fixed :S