View Full Version : Medea SCSI HD causing capture problem in FCP HD


Nawaf Alali
October 24th, 2005, 04:04 AM
This is my system:

G5 2.5GHz
4G RAM
2x 120GB internal SATA
Medea 1.2TB external SCSI HD
ATTO ExpressPCI UL4D SCSI card
AJA KONA LS capture card
FCP 4.5 HD
OSX 10.3.9

My problem started when I wanted to capture 10-bit uncompressed to the SCSI HD. The capture screen would freeze on random frames, and I have to Force Quit it. So I captured a small portion (I stoped before it froze), and tried to play that video on the timeline. I had a horrible drop frames, and error msg saying that my HD is not fast enough to play 10-bit.

So I did a speed check for the SCSI HD (with KONA speed check utility), and got a result of: 10 MB/s for reading writting! So I updated all software and hardware (including SCSI card). Did the speed test again, and the result was: 170MB/s Write, 120MB/s Read. I know I could get better results (up to 200MB/s), but I'm happy with that so far.

Now, I tried to capture DV footage to the SCSI HD, and I'm facing the same problem! The Capture Screen would freeze in random places, causing FCP to freeze, and I have to Force Quit the program.

In the speed test, I graphed the results. The speed was constant around 170MB/s, but there was a sharp spike (1 frame long), where the speed drops down to 40 MB/s. I know that 40MB/s is still fast enough for DV, but do you think that's what causing the problem?

By the way, when I capture to the 2nd internal SATA HD, I face no problems whatsoever (even at DVCPRO50 compression). It only happens with the SCSI HD.

I wanna know if the problem is caused by "SCSI card, SCSI HD, or FCP", before I start contacting the companies.

Nawaf Alali
November 3rd, 2005, 02:39 AM
it turned out to be a Heat problem. I guess the room wasn't cold enough (i'm running 2 machines, SCSI HD, and bunch of other devices). When a SCSI HD starts heating up, it will starting giving problems. So I froze my room, and now everything is working fine.