Dropping Frames Constantly

[wizz]

Hi all,

Got my Marvel G400 and decided to buy a new Maxtor 27 Gig drive as my video drive. Connected it all up but in the last three weeks i have not been able to capture in Mediastudio 5.2, AVI_IO or PC-VCR without dropping frames. Matrox drive benchmark reports the drive at over 9 Mbp/s with my 13 Gig system drive at over 8 and yet i'm dropping frames, not badly but enough for concern.
I thought it might be the the ATA cable which is the 40 pin one instead of the 80 pin for UDMA66 drives??? Does anyone have the Maxtor and do you have the same problem??

Thanks

Tony

[BrianP]

Dropped frames could be the result of any number of things. First you need to do some basic steps, like:
-capture to a different drive letter than the system drive
-tweak your system.ini settings for vcache
-make sure no IRQs are shared
-have the latest (and correct) drivers
-disable networking while capturing

All these tips are found somewhere on this site.

As for my own story, I have a Marvel G200 and despite everything I tried, it failed to capture without dropping several frames per minute even at low quality settings. Sometimes you just get a lemon. I bought a Canopus DV Raptor and never had any more problems.

[This_Idiot]

Wizz,

Can you give us a clue on how many frames you are dropping ? The occasional dropped frame is almost inevitable, all of us suffer from it occasionally. Sometimes folks write to me because they dropped 1 frame in 30 minutes capture and want to know why.

There are bounds to the acceptable, and we each have to make up our minds what those bounds are. I've never suffered unduly from dropped frames, even with fairly basic setups. Which may mean that my personal criteria aren't as stringent as some other people.

[wizz]

Chris,
I've worked hard on my system and yesterday it dropped 59 frames after 1 hour of video capture in PC-VCR. I'm going to try AVI_IO next and see what happens.
I have to say my previous Marvel G200 never dropped frames with the 10.2 Gig Quantum Fireball drive, i mean never dropped any frames. You see, i edit in multi-camera footage in Media studio so i can capture up to 3 hours of video and mostly with no frames dropped with the G200 and the system is more than powerfull enough so i'm wondering what's up with the new card.

Tony

[Brian Ellis]

Wizz

Tell us everything you can about your system and how it is set up, please.

There are some mother boards which cause frames to be dropped or worse and, I suspect, about 1001 other causes, many of which are avoidable.

My first comments: assuming your C: drive is used for booting and is the IDE 0 master. Is your new drive the IDE 1 master and set up properly? Do you have a fixed swap file and on which drive? Is it defragged? Do you have a fixed vcache of 20-25% total RAM? Is your video partition newly formatted? Are you sure that your DMA is working as it ought? These are always the first questions asked, in these cases.

Another thing: download the latest version of Sisoft Sandra 99 (FOC at several sites) and run it. One of the tips may give you a clue. And tell us your benchmarks, especially Drives and Memory.

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Brian (the terrible)

[wizz]

Brian, Chris,

I did everything you suggested and nothing worked. Curiously out of frustration, i changed the read ahead optimization back to full and changed the role of the PC to Network server in system properties. I have captured up to 2 hours of video without dropping a single frame, must be a qerk of the Maxtor drive because i don't understand why this should work.

Tony

[jeff b]

I don't know about anybody else, but dropping 59 frames in one hour sounds an awful lot like clockwork, ie- disable the little clock in windows system tray and see if that's what the problem is.

[Brian Ellis]

Wizz,

Good point, often overlooked, about making ALL computers "Network Servers", even if they are stand-alone. I've done this systematically to all my and my companies' computers. It does improve read performance from the hard drives (by a tad). It may also improve write performance, but am not sure on this.

How increasing the read-ahead can improve the write-ahead, unless there is a crystal ball in the DMA, makes the mind boggle

Still like to know your Sandra benchmarks (good for comparison).

Brian

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Brian (the terrible)