PCI RAID card for HD content (1 Viewer)

[eetaylog]

Would this Sata RAID card be quick enough to be able to stream HD content (bluray movies) over a network if i set it up with RAID1 arrays?? It claims 150Mb/s transfer rate, but im not clear what speeds HD content needs...

4 Port Serial ATA RAID 0,1 PCI Card - Misco.co.uk

 

[AIstudio]

This is what I have picked up.

According to the Blu-ray Disc specification, 1x speed is defined as 36Mbps. However, as BD-ROM movies will require a 54Mbps data transfer rate the minimum speed we're expecting to see is 2x (72Mbps). Blu-ray also has the potential for much higher speeds, as a result of the larger numerical aperture (NA) adopted by Blu-ray Disc. The large NA value effectively means that Blu-ray will require less recording power and lower disc rotation speed than DVD and HD-DVD to achieve the same data transfer rate. While the media itself limited the recording speed in the past, the only limiting factor for Blu-ray is the capacity of the hardware. If we assume a maximum disc rotation speed of 10,000 RPM, then 12x at the outer diameter should be possible (about 400Mbps). This is why the Blu-ray Disc Association (BDA) already has plans to raise the speed to 8x (288Mbps) or more in the future.

SO reading that I cant see why it wouldn't work, as long as you have a good network with good speed??

I haven't tried streaming HD content yet. TV and DVD are fine, as is music.

Good luck with your quest

Regards

Kev

PS I think it may need a little more reasearch as there seems to be conflicting information. Some say that you need a LOT higher data rate???? I tried it over my Lan and HD/Bluray material stutters badly, but my setup is with a different Raid card & my network is only 10/100 lan.

 

[eetaylog]

cheers for the reply, seems from reading the above that the card might be on the limit of minimum specs, though i dont totally understand where it gets some of its bit rates from.

my network is wired with cat5e cable throughout so it should be good for speeds up to 1Gb/s, so really the only bottleneck in the system would be this card.

can someone confirm either way.

cheers.

 

[Malingo]

Network speed is more the limiting factor for streaming HD content, I don't think you will need a RAID array.

If I am not mistaken, a current HDD has a speed of around 50-60MByte/s.

Also, as far as I know, BluRay movies use a datarate of 36Mbit/s. But for arguments sake, let's use the doubled rate of 72Mbit/sec. That is 9MByte/s, so a normal HDD should be speedy enough to serve 4-5 HD streams.

 

[eetaylog]

Network speed is more the limiting factor for streaming HD content, I don't think you will need a RAID array.

If I am not mistaken, a current HDD has a speed of around 50-60MByte/s.

Also, as far as I know, BluRay movies use a datarate of 36Mbit/s. But for arguments sake, let's use the doubled rate of 72Mbit/sec. That is 9MByte/s, so a normal HDD should be speedy enough to serve 4-5 HD streams.

how comes you dont think i should use RAID? id like to use an array as 1Tb volumes arent going to be enough i dont think (ive got a few hundred DVDs i want to back up)

 

[Malingo]

I thought you consider the raid for speed, where you don't really need a raid.
If you consider it for size, it absolutly makes sense.

In any case, you shouldn't get any speed issues with this card.

 

[AIstudio]

If you are going to use a raid card for 1Tb drives or over, make sure that the card supports the LBA as I found out the hard way.
I was using the onboard raid contoller of my Asus striker II Formula to control 4 x 500gb drives in raid 5. I then wanted to upgrade to 4 x 1Tb drives. Fine I thought, but the onboard raid controller didnt support the LBA that is required for larger drives, so I had to buy a rocket raid card that did. Cost me an extra 100 at the time.

Heres the card I had to buy in the end HighPoint RocketRAID 2640x1

Hope that helps


Regards

Kev

 

[qventin]

Actually if you plan to stream over a network the bottle neck will be not the HDD, but the network itself. Running a Gigabit connection will give you 30Mbytes per second if you are lucky (yeah, specs get you faster figures, but that's real life), otherwise you'll get aroung 20. On a standard 100Mbit lan it's 11Mbytes at max. So what's the point is the fast RAID?

 

[funkstar]

A single hard drive will easily handle HD streams. A current hard drive will put out in the region of 50-60MegaBytes/sec, as that quote says, BluRay movies can peak at 54MegaBits/sec or about 9MegaBytes/sec.

That quote gets confusing because it goes on to say about 8x readers. This is just like CD and DVD drives, you can get Nx readers, but their original use as music or video media does not need more than 1x speed (BluRay would be different and require 2x read speeds for movies though wouldn't it?).

So, you won't need a RAID card for speed, but you might for capacity. However, I would be inclinded to just use the built in Windows software instead. Set your drives up as dynamic disks, and you can span one drive letter over multiple physical drives. This will not give you data redundancy, so if you drive dies, you may loose all your data, but it does mean you can have multiple terabytes of data all appear as a single drive to MediaPortal.