Hi,

I'm hoping I can get some help on a problem I'm having with my Gigabyte P35-DS3R. I use my computer for audio production, and consequently need excellent audio performance.

There is a program called DPC_latency checker, (http://www.thesycon.de/deu/latency_check.shtml), that checks how well one's computer can handle real-time streams, such as realtime audio or realtime video. When I run the program on my computer, I get periodic spikes every 5 seconds or so which spike up to about 600us. Even though this number is within the program's acceptable limit, it is no good when I'm trying to run my audio applications at extremely low latency, as the problem gets worse as the CPU gets loaded, and I start to hear little audio pops and clicks.

I've tried disabling every possible device (including the soundcard) and stopped every service from MSCONFIG, but the problem persists. I'm almost sure it is not caused by my soundcard, which is a pci RME9652.

Another interesting thing that happens is the problem gets worse if I change the motherboard BIOS from f9 to f10. My latencies go up to 750us with f10.

I had my friend run this little program on his Asus P5K and he gets latencies of ~30us, which is what I would expect from a modern motherboard/CPU. I've also tried using a Q6600 (I have a e6750), and the problem is worse - I get ~760us. This seems suspiciously proportional to the decrease in fsb speed.

I'm wondering if anyone has any insight to share, and if anyone can try running the program on their computer and posting the results. I'm in contact with Gigabyte, but so far they refuse to try to duplicate my problem and instead are trying to tell me that it's my setup.

Thanks!
Erik

Oh yes, my computer config is:

Gigabyte p35-ds3r
Intel e6750
2GB ddRII 800mhz
nvidia quadro fx550
dual monitors ( 1x dell 2560x1600, 1x samsung 1920x1200)
Seagate 500gb SATA
rme hdsp9652 sound
Windows XP home
1 ide DVD burner, 1 SATA DVD burner

What are your temps? Is the chipset getting toasty? Have you reset your BIOS to defaults, especially after flashing it to another version?

Temps are normal. Everything is running at stock frequencies. I've tried BIOS revisions F6, F7, F8, F9, and F10. All are the same, except for F10, which is worse than all the others.

You could try the latest F11 bios. The changelog is:
1. Added new super I/O code
2. eliminated memory adress bug

maybe it helps.. the bios is released jan.9.2008

hehe, nevermind. updated my bios and went from 880us to 1150us maximum... Not exactly an improvement I guess..

wow.... 1150us is really bad especially considering the Asus board did 30us. I think I'll stick with F6! (or maybe I should try F1 and it will be better???)

Gigabyte thus far has still not confirmed that they think this is an issue. I guess most users wouldn't notice this type of problem, so they are choosing to fix other bugs.

Has anyone else measured their system?

I've doing some more searching on this subject and found a german gigabyte forum. it contains a thread with the exact same problem. a lot of people are experiencing this.

here is a google translation:
http://translate.google.com/transl [...] en&ie=UTF8

(I know it's hard reading, but it's easier that german )

I think these spikes are my main cause for my creative audio card to crackle. I'm having there spikes on my p35-ds3 and p35-ds3r.

Maybe trying F1 bios ins't a bad idea.. could you try that estauber?

Success!

I tried F2,F3,and F4, and the problem goes away with all of them. So whatever Gigabyte did between F4 and F6 (F5 isn't available), that was when they broke something.

Thanks for the link to the German post. I feel better knowing that I'm not the only one with this problem. I should have enough ammunition now to write Gigabyte and convince them that they've got a problem. I would like to be able to continue to use Gigabyte boards - I like them otherwise.

Thanks for the help, janwillem!

YES!! SUCCES HERE AS WELL!!

I have the P35-DS3 (non-R) and was experiencing these kind of DPC spikes:

Above picture is with the F11 bios.

Changed the bios to F4 and got these results:


So, estauber! way to go for us!! mny thnx for your effort! I have a P35-DS3R with a lot of audio crackling and haven't tried updating a f4 version of the bios yet. Are your audio cracks gone now?

yes, much better! I hope that solves your problems

And yes, I can now run reliably at 128 samples (3ms) on my m-audio profire lightbridge - and I'm going to test my other computer once I go to the studio later today (same motherboard, but with a Q6600 and a RME HDSP9652 PCI sound card). I'm expecting I'll be able to go to even lower latencies with that since RME has written the driver to go all the way down to 32 samples (0.7ms) - that's really low! I'll post the result tonight.

Thanks again for the help!

OK, measured my system with the Q6600 and RME HDSP9652:

Wow - it works all the way down to 0.7ms without any popping. The BIOS made a huge difference. It barely worked at all before with F6

I have a P35c-DS3R rev 1 motherboard. I'm getting the DPC spikes which make Cubase unuseable. I reverted to the F4 BIOS and the spikes went down a bit but are still hitting 1000us and up regularly and Cubase is still popping. Next I tried BIOS F2 (F3 is not available) and the spikes went way down to where they normally stay at 30us but every minute or so I still get a smike around 500us.

I've disabled everything else I can. Anyone have succes eliminating the spikes with the P35C motherboard? On my old ASROCK motherboard I always ran at .6 latency without any pops and I did a major upgrade to a Q6600 and fast RAM but the DPC spikes are killing it.

best!
Paul

Here are my results on a P35-DS3L:

I wonder if Gigabyte is working on a fix for the future BIOS revisions for this DPC spiking problem. I found the F1 BIOS works best for me with latencies usually below 12us which is great for Cubase. I did however notice that when I open CPUID that I get the spikes again which tells me whatever BIOS calls CPUID is making is triggering the problem.

It strange that later BIOS versions are getting progressively worse when Gigabyte only reports basic fixes for each version.