Stuttering Video...Again!

[rickgillyon]

Hi,

I've got a problem with stuttering (very small dropouts) in video and audio even when recording only one source. This has been the case ever since I built my system a couple of months ago. I've tried all sorts of things to fix it, and I think I may be getting close, so some advice would be appreciated.

Basically I have an AMD64-based system, XPSP2, Nvidia 6200 GPU, Gigabyte Nforce4 board, 1GB RAM, 80GB SATA2 System drive (that the system sees as SATA), 500GB SATA2 Capture drive (seen as SATA2), plus two Hauppauge 350s & IDE DVD Writer. The HDDs are attached to the Nforce RAID controller.

Now, I've tried all sorts of things to fix the stutters, but at the weekend I tried changing the capture drive to be a PATA drive on another machine on the network. No stutter, at all. Clean as a whistle.

So I got to thinking, maybe it's the controller. The disk is formatted with 64k clusters and should be fast as hell, so I dumped out the IRQs, list follows:
0 : System timer
3 : NVIDIA nForce PCI System Management
6 : Standard floppy disk controller
8 : System CMOS/real time clock
9 : Microsoft ACPI-Compliant System
13 : Numeric data processor
14 : NVIDIA nForce4 Parallel ATA Controller
15 : NVIDIA nForce4 Parallel ATA Controller
16 : Hauppauge WinTV PVR PCI II (Encoder/Decoder)
18 : NVIDIA GeForce 6200 TurboCache(TM)
19 : Hauppauge WinTV PVR PCI II (Encoder/Decoder)
20 : NVIDIA Network Bus Enumerator
20 : NVIDIA nForce4 Serial ATA Controller
21 : NVIDIA(R) nForce(TM) Audio Codec Interface
21 : Standard OpenHCD USB Host Controller
23 : NVIDIA nForce4 Serial ATA Controller *** 500GB
23 : Standard Enhanced PCI to USB Host Controller

As I have marked, IRQ 23 is the controller with my capture drive on it, and it's shared with a PCI to USB host controller. Could this cause the problem?

Device Manager won't let me reassign IRQs, how can I make this controller use (say) IRQ 22? Or am I barking up the wrong tree?

Thanks for any help you can give!!
Rick

[Commodore 64]

"For starters the GA-K8NXP-9 includes an additional Silicon Image Sil3114CT176 SATA I/RAID controller"--Since you didn't specify the model, I just grabbed that off a random website.

There is a thread over at AVS forums and some conjecture that the SI311x are the culprit of HDTV stuttering. And it might not be just related to Avermedia HD cards.

http://www.avsforum.com/avs-vb/showthread.php?t=597238

It looks like you figured this out for yourself, but I just wanted to let you know that your hypothesis is probably correct.

[rickgillyon]

Actually, I have a Silicon Image controller, but I'm not using that one at all! It's the nforce SATA2 controller that's causing the problem. I don't want to move it to the Sil because it's only SATA1, and I paid the money for SATA2...

Thanks!
Rick

[naln]

Originally Posted by rickgillyon

tried changing the capture drive to be a PATA drive on another machine on the network. No stutter, at all. Clean as a whistle.

20 : NVIDIA Network Bus Enumerator
20 : NVIDIA nForce4 Serial ATA Controller

23 : NVIDIA nForce4 Serial ATA Controller *** 500GB
23 : Standard Enhanced PCI to USB Host Controller

Device Manager won't let me reassign IRQs

Looks like you have already identified the problem source. The shared IRQs for both SATA controllers seems strange. Have you tried manual IRQ assignments in the BIOS? Try to disable peripherals like Serial ports etc that you do not use- may help in reducing auto-assigned IRQ conflicts.

Good luck.

[rickgillyon]

Thanks for that, but I've already disabled the things I don't need (as far as I can tell). I can't find anywhere where I can manually set IRQs in the BIOS, is this normally possible? Oh, I see, seems to be only for PCI slots (which are OK), and one other for "on-chip". The mobo model is a Gigabyte K8NXP-SLI BTW. I guess when I'm back home (Friday...) I can have a play with that one, but I don't hold out a lot of hope!

Rick