Very high CPU usage with PVR-150 and GBPVR

[ubu]

I've been struggling with this problem for months. I've tweaked my GB-PVR set up within an inch of its life, tried different drivers, decoders, video cards, switching cards from slot to slot, and I still get cpu usage between 80% and 100% when watching live TV. I'm pretty comfortable with the software side of things but hardware problems just make me feel like I'm stupid. I could really use some help here.

As you can see from my signature, my HTPC, while not a screaming beast, should be adequate for the job and there's nothing I can see that's "non-standard" about it. Here's what I see when running Process Explorer from a remote XP session:

Code:

[U]Total[/U]        [U]DPCs[/U]               [U]Interrupts[/U]
GBPVR menu (idle):     3-10%        1.5%                1.5%              
Recording playback:    35-45%       1-3%                1-3%
Live TV preview:       85-100%      30-40%             20-30%
Timeshift (paused):    55-65%       20-35%             10-25%  
Timeshift (playing):   75-95%       20-35%             10-25%

The portion of the total that's not DPCs and Interrupts is largely taken up by gbpvr.exe. My wifi network software blips in with 1.5% every few seconds and Process Explorer itself takes 1.5% every so often. I'm currently running a clean 97.9 install under a clean XP SP2 install with newly installed Forceware, Hauppauge 2.0.43.24108, latest Intervideo non-CSS decoders, latest wifi card drivers. I played "musical chairs" with the PCI slots. Nothing. Nada.

Would a dodgy PR-150 card cause this symptom? Could my mobo just not like my choice of cards? BIOS something or other?

I see forum posts reporting 30-40% cpu for live tv on PIII systems so I should be getting as good or better with a P4 I'd have thought. I know that P4s do vary a bit in their architecture. I've got a 2.4 and a 2.23 to choose from and could get my hands on a 2.53...... (OK - now I'm grasping at straws!)

It's not just causing wierd live TV effects but, in my crowded case with the weather getting warmer, CPU temp is touching the wrong side of 50F too often for comfort. :eek:

[csy]

What's your CPU load when doing recording only?
(mine is 2-5% on an ATI550)

[ubu]

What's your CPU load when doing recording only?
(mine is 2-5% on an ATI550)

About the same as the numbers for Timeshift (paused) in my chart. Which figures, I guess, since when timeshift is paused, GB-PVR is still recording but not rendering the captured stream. Also, forgot to mention that playing an mpeg or a stream with VLC or WMP is down more in the 15-35% range. So, while my CPU usage seems generally a bit high, it seems to get really outrageous when the capture card is in play.

2-5% is pretty impressive. I'm not getting that low even at idle. I'm not well versed in AMD CPUs. Is a a Sempron 3000 comparable to my P4 2.4gHz?

[csy]

The 2 CPU's are probably fairly close (for this discussion).

My playback is close to yours, 20-40%

It definately looks like you have something seriously wrong with the PVR150.

[csy]

Is something screwed-up and doing software encoding?

What does GraphEdit show on the recording side?

Are you using Comskip or ShowAnalyzer running while recording? (what happens if you disable them?)

[ubu]

Is something screwed-up and doing software encoding?

I had to configure a new hard disk for my OS/Software drive so took the opportunity to do a real clean "hermetically sealed" install so literally just have the components mentioned in my first post installed. So "long forgotten freeware codecs" and suchlike are unlikely.

What does GraphEdit show on the recording side?

...and that includes not having installed GraphEdit yet. Last time I ran it (against my old 96.x setup) it showed nothing abnormal - just the pieces I expected to see. And this CPU clocking problem has been with me all along. Seems a bit worse with 97.9 but that could be my fevered imagination.

The only exception to the above is that I did install the latest version of Purevideo to try out some of what we had discussed in another thread. However, since it seems to be a bit of a CPU hog, combined with my CPU problem, it made watching live TV (though very sharp and clear) virtually unwatchable (stuttering, losing audio, etc.) while the Intervideo decoder seems to struggle along in "just" watchable fashion.

It definately looks like you have something seriously wrong with the PVR150.

I guess I could try sticking the PVR-150 in a different box, install GB-PVR et. al. and see if I get the same problem. Sad, if true, since it's probably just out of warranty by now. If it works OK, though, that would probably indicate that swapping mobos or CPUs might fix it?

[ubu]

My playback is close to yours, 20-40%

How much of that (and of your live tv percentage) is shown as Interrupts and DPCs? Don't really know how to interpret this but I'm thinking the high proportion of my cycles spent there is actually telling me I have some sort of hardware issue. Does anyone know what causes a procedure call to become "deferred" and what that would indicate in the real world?

[csy]

I'm a bit dumb when it comes to DPC's and interrupts.

How do I measure them?
(I don't see them on the Windows Task Manager - Performance tab)

[stefan]

You would have to download process explorer - from sysinternals?

[ubu]

You would have to download process explorer - from sysinternals?

Yes, that's what I'm using (somebody recommended it to me here back in February when I was wingeing about this same problem :o). I don't know how Task Manager shows them. I guess they're rolled into the System Idle Process task. I'm assuming Interrupts is showing actual hardware interrupts but I'm less clear about Deferred Procedure Calls.

I do notice that when first watching live TV most of the cycles are shown being used by GBPVR and the DPC percentage is low. But within a few seconds, the DPC percentage grows and the GBPVR percentage diminishes. I'm just wondering if that's normal (does the decoder's activity show up as DPCs, for instance) or the symptom of something dire.