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**Dr Mordrid** · 21 August 2002, 12:50

1. most VIA IDE drivers, for lack of a better word, SUCK.

2. VIA chipsets SUCK, as in they don't have enough bandwidth to let most HDD's stretch their legs. I've seen 20-25% improvements in HDD write speed just moving from a VIA to an Intel or SiS chipset.

3. I'm the guy with 90 mb/s. I get it by using a Promise 4 channel RAID card (TX4, SX4000 etc.) with four Maxtor D740X 7,200 rpm HDD's.

4. if the Maxtor HDD is an ATA100 or faster then it may have Write Verification turned on. This is normal, but it's supposed to turn itself off after 10 system powerup cycles. Unfortunately it doesn't always go that way. When left on WV cuts the drives throughput by almost half. Maxtor has a tool, WVSET, for turning it off manually.

5. turn off SMART in the system BIOS. This too slows down HDD's read/write performance.

Dr. Mordrid

**RhinoZ** · 21 August 2002, 19:43

I've read from this place that Via sucks.. but I didn't think that it would affect HD performance...learn something new everyday with you guys.

But a RAID question then.
Do you Raid the OS drive?
Or do you have to have 1 drive for the OS, programs etc and 2 drives RAID for video capture.

I'm hoping to get a Raid card for my new computer setup that will use the MSI 745 Ultra board

But I really don't know much about RAID as I always thought of it as a server requirement rather than helping me get better HD performance in capturing.

Thanks

**Dr Mordrid** · 21 August 2002, 20:11

NO, I never RAID the OS. Better left normal.

I use either;

1 drive for OS (primary master), 1 drive for capture (secondary master) and 1 drive for exports (primary slave). CD or DVD decks go on a separate IDE controller (Promise Ultra133 TX2 mostly) plugged into a PCI slot.

or

1 drive for OS and 1 very large & fast RAID array for capture & exports. Right now this is filled in by either a Fasttrak100, Fasttrak TX4 or my new Promise SX4000 RAID 5 card.

The first setup is better for hardware realtime boards like the RT.X100 while the latter is better for non-realtime using analog video.

RAID 0 (striped array) adds the sizes of identical drives to give you a load of capacity. Each drives speed is also multiplied so the array ends up faster than a single drive would be. Handy for capturing and exporting high bitrate analog video, but not really necessary for DV.

RAID5 is a striped array like RAID0 but with distributed parity across all the dirves so lost data can be rebuilt.

Dr. Mordrid

**KRSESQ** · 21 August 2002, 21:32

Hey, Doc. Have you experienced any problems with those D740X's? I have one of the 80 gigs on my secondary IDE controller and I've been getting bad cluster warnings from scandisk all over the place. Right now it's reporting 16 MB in bad clusters. Seems like every time I try to capture something new bad clusters pop up (well, almost. My last cap test came out okay).

If it gets much worse I'm sending it in for replacement.

Been having appalling luck with Maxtor lately. Had to send both my 30 gigs in for replacement.

Kevin

**Dr Mordrid** · 21 August 2002, 22:30

I have over 30 Maxtors here, with about 8 of 'em being D740X's. Have about 12 Maxtors "retired"....still functional but smallish ATA33's and ATA66's I keep for backups. No problems at all in any of 'em.

Dr. Mordrid

**landrover** · 22 August 2002, 01:56

KRSESQ,

Is there by any chance a possibility that your drive gets too hot? Maxtor have a very good reputation for reliability over speed. Avid recommends using Maxtor drives as an alternative for their own brand (which by the way are Maxtors in an Avid box I guess).

landrover

**RhinoZ** · 22 August 2002, 05:45

Landrover,
Looking at your system, do you do any capturing?
You have a faster PC than mine, but you don't use RAID for your drive. I'm just wondering what size are you capturing at.

Thanks Dr. for the info and advice as always.

So in the first setup you don't use a Raid card for the HD, you use the onboard HD controller and get another controller for the cd & dvd.

And in the second setup can 2 drives work in a RAID array for analogue video?

Thanks Z

**Dr Mordrid** · 22 August 2002, 06:00

That about sums it up. When working with DV the bitrates are so low (3.5 mb/s) relative to working with analog (10-30 mb/s) that you really don't need a RAID much.

When working with high bitrate analog using multiple streams it's a different matter. In this case one can easily require 40-80 mb/s reads to do previews of compled F/X stacks, not to mention the throughput overkill necessary to do uncompressed captures without drops.

RAID's have many flavors. Here are a few....

RAID 0's (what is typically used for video) consist of 2 or more drives that are striped, meaning the drives are written to in an interleaved manner (basically: multiple drives are written to at once). This is why then are faster than a single drive. Their capacity is also added together so that a RAID with 2 drives is twice as large as its single constituents, and so on.

In striped arrays it is best to have identical drives. Any size mismatches will cause the larger drives to be treated as if they had the capacity of the smallest drive in the array, which is a waste of capacity.

RAID 5's are a striped array where there is parity used to provide data redundency. This means the array has the ability to reconstruct data in the case of corruption. In RAID 5 this parity information is stored on all drives in the array (aka: distributed parity).

RAID 3's are also striped arrays with parity, but in this case the parity is not distributed but is instead stored on a dedicated parity drive.

If you create an "array" without striping you have a JBOD (just a bunch of disks). JBOD's can be from 1 drive to as many drives as the card can connect to. They have additive capacity but there is no speed increase because only one drive is written to at a time. When one drive runs out of space the next in line is written to, and so on. This is the only type of array where you can mix & match drives of different sizes without any side effects.

RAID 1 is where there is mirroring; meaning the information in one drive is copied in realtime to another drive. Think of it as a realtime backup. Most decent RAID cards will automatically switch to the duplicate if the primary fails.

RAID 0+1 is a striped array that is mirrored to another striped array.

The combinations can get really complex in that with some high end cards you can stripe together separate RAID 5 or 3's in what is called a RAID 50 or 30 or....you get the idea.

Dr. Mordrid

**RhinoZ** · 22 August 2002, 06:25

Hi Dr. Morbid,
Sorry, I meant to say would just 2 Raid drives work for anaolgue capture? And what kind of speed would I expect? Would it reach the 10-30mb/s that I'm looking for.
Also if you can answer this off topic question.
How do some people with similar system specs as myself brag about how great they are capturing with AV_IO using huffyv?
Thanks again

**KRSESQ** · 22 August 2002, 07:19

LRover:

I don't think heat is much of a problem as

a) When I prepped my case I drilled extra vent holes in the drive cage,

b) I had 3 drives in the cage originally with no probs and now have only two,

and c) I haven't had the cover on my machine for weeks. Yeah, I know, bad idea. But it seems like every time I put it on, I'm taking it off again within a few hours for one thing or another.

Sort of like a motorhead leaving the hood off his rod, since he's always got it open, anyway.

Kevin

**landrover** · 22 August 2002, 07:35

I capture PAL CIF with HuffYUV 90% of the time using AVI_IO. The P3B-F only supports UDMA33 and yet the Maxtor drive captures flawlessly. If I need full size video, I capture hardware MJPEG in Win98. Therefore I don't need RAID and not even a 7200 rpm hard drive.

The Avid Media Composer uses RAID 0+1 on 4 Avid 68 gig drives, but that's for broadcasting purposes. At home my main sources are cable and Hi8.

landrover

**Dr Mordrid** · 22 August 2002, 08:10

Originally posted by RhinoZ
Hi Dr. Morbid,
Sorry, I meant to say would just 2 Raid drives work for anaolgue capture? And what kind of speed would I expect? Would it reach the 10-30mb/s that I'm looking for.
Also if you can answer this off topic question.
How do some people with similar system specs as myself brag about how great they are capturing with AV_IO using huffyv?
Thanks again

Two fast drives in a RAID0 is plenty for capturing analog. If one uses AVI_IO with HuffYUV full frame only requires 10 mb/s, which many of the newer single drives can handle easily.

Still, it's best to have much more drive bandwidth than is necessary when capturing high bitrate video. This also allows the easy use of image sequence animations (often used as the output of 3D programs) and still get fast previews. These have a bitrate of ~30 mb/s and thus RAID's are very handy for this.

Dr. Mordrid

**TnT** · 22 August 2002, 13:25

I've been capturing analog full frame (NTSC) with just a Seagate Barracuda IV 80GB and I only drop 1 frame out of every ~1200, but I believe this is due to the SBLive Value I am using (or do I have incorrect fps? haven't had time to check). Anyways, it would be better to capture using RAID, but from my experience it isn't necessary if you have a good mobo and hard drive (unless you need to capture a lot of footage at a time).

I used to use have a mobo with a Via chipset and 3.4MB still sounds really low.

**Dr Mordrid** · 22 August 2002, 14:21

Ever try capturing full frame uncompressed RGB with a single drive?

Dr. Mordrid

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