DPC Latency Enigma

[Spider-Vice]

Hey all, I'm new here and I don't know if this is the right section but here goes. A while ago I had plenty of noise on my headphones, I seemed to think the motherboard was dying, didn't know anything about DPC latencies yet, well it happens that it once froze while doing a speed test and from there it died completely. Then I got a Gigabyte GA-G41M Combo (I had an Asus P5B-SE), the problem seemed gone but I still didn't know about DPC latencies until I started experiencing sound pops and clicks. I researched and found out about DPC latency and also found out that disabling the power saving functions in the BIOS solved the problem. Right, I did that, and the problem was "solved".
So why solved between quotes? It seems that it's not completely, my graphics card is an nvidia GT 220 and I'm forced to use another because the GT 220 just goes completely crazy in latencies, reaching yelllow lots of times and as the spike is so big (like 90 us to suddenly 1200) it still causes freezes and sound pops. With that I changed back to an 8500 GT I had and these pops were solved... Not completely. The problem with the 8500 GT is softer but not completely fixed, I still feel the computer is unstable and sometimes sound keeps popping from time to time and stuff freezing. With LatencyMon (GT 220) I found out it was the nvidia kernel driver, so I switched the graphics card back as I said above. With the 8500 GT, I get some higher latencies on ndis.sys and tcpip.sys, also ataport and usbport but not very high.
Later on I start seeing nvidia kernel issues again, yet not so heavy, that's what starts to cause some sound pops and freezes again. As I'm a gamer, I decided to try to ignore that problem and switch to the more powerful GT 220, right, I could play games but until yesterday and today, the headphones started making noises again, it happens it starts spiking to yellow as I described earlier on the text, yet not as much but it's annoying. Right now I'm with the Intel onboard graphics that came with the Gigabyte but with the nvidia uninstalled yet still on the PCI port. When I play any game, the Direct X Kernel file now also spikes somewhat and the sound makes a pop from time to time. It's not a big deal like I've seen others before but can be annoying for me as a gamer and sometimes audio editor.

Another note, with the GT 220 if I stress my internet, red spikes start crazy happening, yet I only observed this once or twice, and the sound was a mess. Tried reinstalling all, Windows, etc, doesn't seem to solve the problem but it seems there's a mass driver problem somewhere. And one question, can DPC latency kill the motherboard as I weirdly experienced with the Asus? I'm thinking too of getting a new card, as nvidia has done too many problems to me in the past, though maybe a soundcard would solve my problem in sound?

Oh and also the rest of the specs:
CPU: Intel Core 2 Quad Q6600 2.4Ghz
RAM: 4 GB


LatencyMon Log, stopped now. 27 minutes:

Highest DPC routine execution time (µs): 684
Responsible driver: dxgkrnl.sys (DirectX Graphics Kernel, Microsoft Corporation)
DPC count (execution time <500 &#181;s): 36285363
DPC count (execution time 500-999 &#181;s): 33
DPC count (execution time 1000-1999 &#181;s): 0
DPC count (execution time 2000-3999 &#181;s): 0
DPC count (execution time >=4000 &#181;s): 0

Highest ISR routine execution time (&#181;s): 44
Responsible driver: dxgkrnl.sys (DirectX Graphics Kernel, Microsoft Corporation)
ISR count (execution time <250 &#181;s): 77388014
ISR count (execution time 250-499 &#181;s): 0
ISR count (execution time 500-999 &#181;s): 0
ISR count (execution time 1000-1999 &#181;s): 0
ISR count (execution time >=2000 &#181;s): 0

Highest pagefault resolution time (&#181;s): 185723
Hard pagefault count (total): 130302
Number of processes hit: 4
Pagefault count of hardest hit process: 100992
Process with highest pagefault count: svchost.exe (PID: 4252)

NOTE: some processes were hit by hard pagefaults. If these were programs producing audio, they are likely to interrupt the audio stream resulting in dropouts, clicks and pops. Check the Processes tab to see which programs were hit.

Note: execution times may be calculated based on a fixed reported CPU speed. Disable variable speed settings like Intel Speed Step and AMD Cool N Quiet in the BIOS setup for more accurate results.
Reported CPU speed: 2400 MHz

Thanks. If my post sounded confusing, sorry I'm Portuguese.

 

[mfenn]

Gamer and GT 220? Does not compute!

Anyway, there is a fairly well known issue between some Intel 3x/4x chipsets and Nvidia GPUs that results in high DPC latencies. Can you get your hands on an AMD card?

 

[Spider-Vice]

Oh thanks for explaining, guess it is a chipset issue. The next card I'm buying is an ATi/AMD indeed, so right now I can't get my hands on one. Also I know GT 220 and gamer does not compute
The ATi I'm getting is the HD 6790 but that's all I can afford for now and it's better than the GT 220, way better. I just found it odd that it somewhat happened with the Intel but didn't really cause sound pops, yet I got a red or two.

 

[mfenn]

To actually have an audible pop in your sound, you have to be playing music or whatever when you get a really bad spike. Even integrated audio chips have big enough buffers these days that a short spike won't actually cause the chip to run out of audio data (which is the pop that you hear).

 

[Spider-Vice]

Yeah I listen to a lot of music so it's noticeable when it happens.

 

[Spider-Vice]

I'm going to revive this topic to ask something. On HD Tune whenever I click on the temperature stats, my PC freezes for a while before showing the graph and DPC shoots up to like 2 ms. It happens on both hard drives and on my main sometimes it even says it has no temperature statistics. This also happened on my old motherboard (Where I also had very big latency because of the speakers noise).

 

[Cerb]

What Forcewares are you using? I was a Hell of a time with 275.xx stuttering and audio skipping, and ended up reverting to 257.xx (what I upgraded to 275.xx from). The symptoms and fixing were obvious enough that I didn't bother running the latency checker. AFAIK, the 275.xx drivers are still the current ones on Windows Update, and a quick Googling shows others with measurable increases in latencies coming from 25x and 26x drivers to 275.xx, in which reverting fixed it. I just reinstalled (100&#37; my fault, being an incessant tinkerer ), and the 275.xx, acquired by Windows Update, acted the same as before. The new 280.xx seems fine, though.

You may want to try updating the mobo BIOS, if it's not nearly the newest, as well. I know GB acknowledged some latency problems, and set about fixing them in BIOS updates for some boards (mine came with the revision before they broke it, so I'm leaving it well enough alone ).

Finally, in some cases with HDDs, disabling C1E and EIST can fix them, though this means your processor will run hotter when idle.

 

[mfenn]

I'm going to revive this topic to ask something. On HD Tune whenever I click on the temperature stats, my PC freezes for a while before showing the graph and DPC shoots up to like 2 ms. It happens on both hard drives and on my main sometimes it even says it has no temperature statistics. This also happened on my old motherboard (Where I also had very big latency because of the speakers noise).

That's pretty normal (same thing will probably happen when you open CPU-Z). Any procedure call that has to go out can query stats from a device can be really slow. Such procedures shouldn't get called in normal operation though (i.e. when you're not looking at stats).

 

[Spider-Vice]

Oh okay, thank you for the fast answer. Now I'm just trying to get my hands on an AMD card and report results.

Cerb: I don't think it's really a driver issue, they seem pretty stable. Also the motherboard BIOS is the latest from October 2010 and it's the same one listed on the GB website. EIST, C1E, etc. is all disabled.