Dropouts caused by Partitioning Drive?

FrankM wrote on 8/21/2002, 4:56 PM

I now get frequent dropouts when capturing video, although I rarely got dropouts before.

The only change I’ve made on my PC is to partition the drive using Partition Magic so that I can have a separate partition, E:, for all my AVI files. All my programs, including VV3, reside on the C: drive.

Could this cause the dropouts or should I search for another reason?


Chienworks wrote on 8/21/2002, 5:03 PM
Sad to say this, but you may actually be causing your hard drive to work harder now than it had to before. You've now guaranteed that the head has to move from one partition to another whenever there is an access to the windows partition, whereas before it might have been writing/reading video data very close to the windows data.

Ideally, you need a separate phsyical drive if you want to avoid this sort of problem.
JumboTech wrote on 8/22/2002, 6:51 AM

I've partitioned my drives with PM and not had a problem. Any chance that DMA somehow got disabled during the process?

FrankM wrote on 8/22/2002, 9:09 AM
There I thought I was helping by having a separate partition just for the AVI files and now I learn that it may be causing the problem.

I checked the DMA and I'm not sure whether it is still enabled. I know it was enabled in the past because I recall checking it after reading all the comments about DMA.

Can you look at the following info from my WindowsME PC and tell me IF my DMA is still enabled....

Under System Devices > Device Mgr > Direct Memory access Control Properties I see:

DMA Controller
Reserve Memory
The block for Reserve DMS Buffer is blank
Address Restrictions
The block for Restrict DMS Transfers to Memory Below is blank
The blocks for the choices 16 MB or 4 MB are greyed out.

Does that info tell you if my DMA is enabled or not? If not, what exactly do I do?

Also, if it will solve the problem, I will gladly remove the separate parition. I just did so that it would be easier to defrag the AVI files so they will run more easily.

Thanks again for your advice.


BillyBoy wrote on 8/22/2002, 9:46 AM
You didn't say what version of Windows you're using. For example with Windows XP you can check DMA settings from Device Manager. The link below gives some basic how-to. Generally you want your hard drives to use the highest DMA setting they support so they operate at the highest speed. I have a 80 GB hard drive as master and a 100 GB as slave on my primary IDE channel using Ultra DMA mode 5 which is very fast. Windows being Windows, if it encounters errors, without telling you will drop down to slower mode if errors are reported. You can check if your drive was dropped to a slower setting (from Device Manager) then check for cause by looking at your System Event Log if you're running Windows XP.


For video editing you are much better off having a SEPERATE hard drive which you use to capature to and also use for print to tape if you're making files rather than printing back to your digital camera from the timeline.

Why? Because as you've done, making a seperate partition on your root drive, you're forcing your drive to work harder and run slower because it will need to jump back and forth to reposition the drive's heads constantly. That all by itself may inject dropped frames. By setting up a seperate hard drive, not just a seperate partition, you avoid the issue. Also because of how Windows works your root drive tends to need much more frequent defragging, so again, if you use only a single drive and it becomes severely fragemented that too will slow it down enough to perhaps cause dropped frames.
FrankM wrote on 8/22/2002, 1:12 PM
I'm using WindowsME.

I understand the comment that a separate hard drive would work best.

However, would I avoid the problem if I install VV3 on the new partition and run VV3 from the same partition where the AVI files are?

Also, from my description above as to what my WinME Device Manager, Direct Memory Access Controller Poperties, screen shows, does that answer the question re DMA being enabled?

I apologize if these are newby questions, but I am confused.

BillyBoy wrote on 8/22/2002, 2:17 PM
I haven't used ME for awhile, so I'm guessing from memory. I think if I remember right if your right click on any drive letter from within Windows Explorer there is a check box that indicates if or not DMA is enabled. Aside from that not having XP, you could check your CMOS. Perhaps someone using ME can give a more detailed answer.

As far as installed VV on the same partition no, that won't help since your system will still need to access the drive Windows is on to use its Swap File. I think even moving the swap file to the same partition wouldn't really help. Capturing or writing video frames is very intensive and even a few milliseconds delay can result in dropped frames.

FrankM wrote on 8/22/2002, 5:38 PM
In WinME a right click on Drive C: and E:(the partition) brought up Drive Info. A click on Drive Info brought up the DMA info. DMA *is* enabled on both drives. Thanks for the tip on how to check the DMA.

So much for the DMA being the solution to my dropout problem. Oh well.

I guess I need to delete the unhelpful partition and go back to long defrags on the C: drive.

Thanks everyone.
Lajko wrote on 8/23/2002, 1:35 PM
I have an 80 gig main drive partitioned as 3 drives for the same reason and I get all the same problems. I went through a lot before I discovered something with the drive was causing data loss when printing to tape (See message in Problems Printing to Tape!!). ignoring other problems caused while trying to solve it, putting data on a second PHYSICAL drive totally solved the problem printing to tape.

So the best suggestion is to leave your drive partitioned and use partitions for editing space (as time is not important there) and add a second physical drive for capturing and printing to tape. Insure the second drive is on a separate IDE cable from your main drive so nothing will interfere with it. CD on same cable is OK as you wouldn't be using the CD when capturing or printing to tape.