Sat 9 May 2009
Video Jitter
Posted by admin under computer stuff
[4] Comments
I have been using a PVR-250 card in a Pentium 3 running at 1.2ghz with 2giglebytes of memory for several years now. It has worked well and without incident. Recently I moved the PVR-250 to the last PCI slot because I thought it would make other hardware provisions more convenient.
Yes, convenience is not as important as performance. Shortly after the relocation I began to notice an annoying video jitter. Some video frames were either dropped or distorted.
Today I restored the PVR-250 card to its rightful place alongside the AGP video card. No more jitter.
I am beginning to think when it comes to computers and performance I may be my own worst enemy.
I am not suggesting this is a fix for all occasions, but if you have a PVR and intermittent video jitter or worse, try moving the card to a slot that has a higher IRQ priority. This may be particularly effective if your system is low on speed or memory.
Not quite a solution. The card was moved and the jitter seemed to get better but did not go away. The ability to record did go away. Not sure why but the PVR card would no longer display the video or audio.
Used HWclear, rebooted and tried to reinstall the drives for the PVR. Ran into a problem where the system could not find the PVR card hardware. Relocated the PVR card to the next to last PCI slot in the system and the card was recognized. HWclear used again, reboot, and the drivers were reinstalled successfully and the PVR again displays video and audio.
Currently cloning the successful installation to a spare drive. Once done will button up the system again and hope it will work for a while. This time maybe without the jitter. Will know for sure in a few days.
Well it did not take more than a few hours to discover a REAL problem. Was cloning to the old hard drive that I used when the PVR quit working. Turns out that drive is fried. Perhaps it was working earlier but now it is definately fried. So out it goes with the rest of the trash and we are now using a 10gig wester digital cheapie as a clone backup.
Perphaps a brief description of the setup is in order. In order that I don’t forget once altzheimers sets in.
Got several drives in this machine. A 3.5 inch floppy that gets little if any use. A boot drive either the 27gig or the 10 gig clone, as drive C. Drive C is the workhorse holding a fully updated XP professional with SP2 and all application software. Drive C is not for data or intended to grow. Need to keep is clean and hungry so we can clone it to a 10gig drive. The running drive is 27gig because that is all we had.
Drive D is DVD burner. Does DVDs and CDs.
Drive E is about 250gig and half of a 500gig serial interface drive. Shows up as an scsi but it really is a ATA.
Drive F is the same as E and run off the same ATA drive.
Then we have an external 80 gig firewire drive that sits unused most of the time. This thing is for backup.
We also have a 250gig external USB drive that is also reserved for backup.
We are a little unballanced here having about 300gig of backup for a 500gig drive. Soon we will add another 250 gig for additional backup.
Hopefully we can add the extra backup required before we fill up the two halves of the 500 gig drive.
Still have the jitter but at least the PVR is working. Not sure now where the jitter is coming from. Did not have the jitter a month ago so something has changed. The next step is to install the PVR card in a different machine and see if the jitter goes away.
Maybe test it out on a spare machine running linux. Trouble with linux is that we don’t have the video editing software needed. All that stuff runs under XP. If we had the editing software running under linux we would not need XP.
The jitter finally ended in a complete failure of the TV capture function. At first we thought the TV capture card had failed. It was installed into another higher speed machine and found to work. So now we are using the second high speed machine to do video capture for now.
The offending computer is being used as a Netflix portal and being monitored for further problems. Most likely the real problem is in the buss driver for the PCI buss. Those chips are soldered in and tough to get. The solution is a new motherboard.
Need to find a motherboard with proper documentation and I/O shield of ATX form factor that can use the same processor and memory now on the old motherboard.
That may be more difficult than just going with an entirely new system. Besides, I am not sure that the old memory is not part of the problem. Or for that matter the old CPU might also have a screw loose even though the system appears to work just fine as a netflix portal.