DPC latency spikes on M6300 - help urgently needed please!!

Hello

i've had a Dell Precision M6300 for a few months now, which I purchased as an audio workstation.

I've become more and more frustrated by the fact that I cannot run my audio at low enough latency to allow me to play softsynths from the keyboard. At settings less than 20ms output latency, the audio suffers from clicks and dropouts.

After some research, I was told to try this utility:

http://www.thesycon.de/deu/latency_check.shtml

Sure enough, it revealed spikes in the DPC latency of 2000-5000microseconds, every 10-20 seconds or so, which corresponded to the breakups in the audio.

I have tried disabling pretty much every driver in the device manager (including wifi, network, bluetooth, usb, ATA controller etc. etc.) with the exception of the system deviced, all to no avail.

I updated my BIOS from A03 to A10, disabled things such as checking of the dock's PCI port in teh BIOS, upgraded the video driver, uninstalled all the pre-installed utilities (intel proset wireless, dell quick set), still no joy.

I read on another forum that a user with the same laptop had a similar problem and managed to solv it by manually setting the fan speeds, but I have no idea how they did this.

Please help....I have a string of live gigs at festivals over the summer, the first in 3 weeks, and really really need to solve this problem asap

Any suggestions welcome, many thanks

 

you can use fangui to control the fans, there are posts here on how to set it up on vista x64, but it runs okay on xp and vista32

You could try a sound card in express port or usb? (dont know much about audio im afraid)

fangui v3.1 http://www.diefer.de/indexe.html

 

Thanks, but I that didn't work. Spikes still remain despite everything. I contacted Dell but they just said they couldn't help me and to install windows performance toolkit, which I cannot because I'm running XP Pro and not Vista

 

I ran the DPC Latency utility on my Vostro 1500 and I also got the spikes until I disabled my wireless card in both the device manager and the radio switch on the side of my computer. After I did this the absolute maximum stayed at 289us. Before it would jump to 2285us every 20 seconds or so. I think the Vostro uses the same audio chip, the Sigmatel 9205, so hopefully this information can be of use to you.

 

Thanks for the reply. I have tried disabling the wifi in both the BIOS and the device manager, and using the keyboard hotkey, but that has no effect. As far as I can tell the M6300 has no hardware radio switch???

 

I would like to see what happens if you disable your graphics card, that is if you have the Nvidia card.

 

I tried disabling it in the Device Manager, it made no difference

 

OK, I have tried *nearly* everything and am just about to give up, sell this otherwise good machine and look for something else.

The only glimmer of hope is that for some reason, physically removing the battery and running on AC power causes the DPC latency spikes to disappear. Disabling the devices in the device manager does not help, you actually have to take the battery out.

When I start using applications however, the spikes return at random. I'm wondering if this couldn't be something to do with ACPI. Is it advisable to uninstall ACPI and change the PC to "standard PC"? I'd try it but I don't know much about the subject and really cannot afford to screw up my windows installation now as I have a lot of gigs coming up

 

Sorry about your problems. I wonder if XP may solve your problems, as I'm still thinking that it's the graphics card that is causing your stutters. There is a program that may help you, given that your card is a Nvidia.

One thing you can try is to run on High Performance, and try running a game. I found that a game, specifically MapleStory, allowed my system to have DPC latency below 500, which surprised me greatly. I really can't figure out why it does that either. I can't reproduce this every time. I'm starting to think that Vista is really wonky... XP never had latency spikes.

Exploring Dell's site shows me that you have Vista Business and an odd Nvidia card... could you post your specs to verify? That is, if you haven't sold your Precision yet.

 

Hi ShinyFalcon and thanks for the reply

The machine came with XP Professional installed, downgraded from Vista Ultimate. I have stripped this OS down to the bare minimum for music use, but the spikes persist.

I also made a new partition and installed Vista Ultimate on it, but the DPC performance there is terrible: spikes as before but now a residual level of around 1000 microseconds. I haven't tried optimising this OS though and I use Vista just for office, internet and email

The GFX card in the machine is a Quadro 1600M. I have only used the drivers which Dell supply as the Nvidia website doesn't allow me to download any and says I must get them from Dell