Multi Render trouble

Hi All

I I am working on a new machine, Dell XPS 15 w. Geforce GT420M GPU and it show a behavior I have not seen before.

When I have more than one renderer active in on instance of vvvv at a time, the content of the renderers flicker between the renderers, it seems random but mostly the content is reversed.

see attached patch for an example.

On my Dell XPS 16 w. ATI Radeon HD 4670 the same patch behaveas expected.

both systems run win7 64bitand have latest display drivers.

besides this issue the system behave as normal.

Any ideas what it could be?


MultiRenderBug.v4p (7.0 kB)

one more detail

when running one renderer each in several instances the behavior is also as expected.

same behavior in beta23 and beta25.1



a clean install of windows without all the bloatware that Dell has solved the issue.

perhaps we could add a note to the install troubleshooting page about it being a good idea to reinstall windows on systems that comes with preinstalled windows.


hmmmm too quick to update

it was running in low performance mode on the intel GPU. when in high performance mode on Geforce the behavior is still the same :(

any ideas?



I have tried the latest Dell display driver, the latest official Nvidia driver, and the latest driver from

all drivers show the same behavior.

Win 7 64, gtx 570 and your patch runs without problems,

have you checked it on xp 32?
it smells like a dell´s compatibility issue…

good luck

Exact same problem with an Alienware m11x, and GT335M. Seems to be video drivers or Optimus related, anyone has found a solution yet ?
Might have to go down the reinstall route, if no one found a better solution.

sunep, this you fix that issue yet ?

Optimus == Pita

Good idea but I am definetely missing the manual option.


Hi evvvverybody

I have just found this topic…

Sunep said:

When I have more than one renderer active in on instance of vvvv at a time, the content of the renderers flicker between the renderers, it seems random but mostly the content is reversed…

Exactly the same problem here on DELL XPS 15Z with GT 525M
WIN7 64

Anyone has found a solution for this problem???

Thank u

Same problem here, on 520gtxm


I am not sure this problem ever got solved, but I recall something some about completely disabling Optimus in Bios… you could try that.

Thank u for the fast reply…

i tried all the dirty tricks on optimus on a dell xps15z, alternative driver, bypassing the intel chipset. nothing worked.

therefore i came to the conclusion to avoid optimus devices. its rubbish. you will find lots of posts on the net about games not working with optimus machines.

quote:Since the GPU is enabled, the IGP enters a low-power mode, where only the frame-buffer and the conversion circuits are active video. Thereafter, the GPU is to do all the processing, copying the frames already rendered to the frame-buffer of the IGP, which now operates only as a kind of printer, sending images to the monitor.

sound like, there lies the problem, the IGP seems not able to handle multiple images rendered by the GPU.

what “can” help in simple setups (only few renderers) is fiddling around with device (ex9 manual) and the renderers device setting…

Our problem was having a little preview on the laptop screen. It messed up completely. The solution for us was to simply scrap the preview.

MM still seems this problem only happens on 4v tho, so some render/presentation handle conflict could be the issue

I got plenty of other standalone multi window apps and that never occurs.

Few tests:
-1 4v instance + 2 renderers flicker all the time
-2 4v instances (allowmultiple), 1 renderer in each, all fine
-Slimdx multi form standalone tests apps (two renderer per apps, one app for dx9/10/11 to double check it’s not a dx specific version bug, didn’t tried in ogl tho ;) . No flickering, all fine.

i confirm optimus for laptop previewing:
1 4v instance + 2 renderers flicker all the time

optimus cant be disable.
i can switch from my bios between NVIDIA GeForce GT 540M - 1 Go DDR3 VRAM and GM3000, ( Graphics > Switchable or not ) but i cant disable optimus thing from nvidia interface.

This is a VERY annoying thing, and like sunep i disabled previewing.

But for example in a dasiy chain of effects ( uncs structure) or any D9texture outputted fom a renderer for intermediate effect creation, it is ALSO fickering all the time.

Same problem here on a Lenovo W520 with a NVIDIA Quatro 2000M and an Intel onboard Graphic chip.

The Problem only appears while having multible renderers open on the Intel Graphic-chip, which is enabled/disabled by the OPTIMUS-driver. This OPTIMUS system switches between the Quadro gfx-card and the Intel Grahpic-chip depending on my power-settings.

The problem is without Optimus I can only attach one and not two external Displays, which is the nice feature about my laptop. So sometimes I need Optimus…

Since, as mentioned by karistouf, it is not possible to switch this on and off with the NVIDIA-Interface I always have to change the setting manually in the BIOS depending on my Hardware-setup. -> very annoying!

yeah, I had this problem too with my XPS 14, mine was because of the windows theme:

hmmmm same with me.

Classic view => Flickering!

Aero => no Flickering.

Lenovo T420 Optimus

strange …