I put in an order for one of these little PCI Express SATA RAID expansion cards for $20. Here is a great little post by one of the guys in the computer forum I've been hanging out at for this project:
" Programs like HT Tune report the average transfer rate of Seagate 7200.10 drives in RAID0 to be around 120MB/s.
While PCI does allow for a peak transfer rate of 133MB/s it is a shared bus. Meaning any PCI network controller, sound controllers and various other devices that use the bus must also share the 133MB/s bandwidth. So it is unlikely there would be 120MB/s of bandwidth to spare.
Because each PCI Express 1x slot has its own lane is has 500MB/s dedicated to what ever device is plugged into the slot. This means there is loads of spare bandwidth and a single slot can easily support more than 2 drives if need be!
PCI Express comes in a few different modes
PCI Express 1x 250 [500 both ways]* MB/s
PCI Express 2x 500 [1000 both ways]* MB/s
PCI Express 4x 1000 [2000 both ways]* MB/s
PCI Express 8x 2000 [4000 both ways]* MB/s
PCI Express 16x 4000 [8000 both ways]* MB/s "
Wow... only 120MB/s? it sounds slow, did I mess up... maybe these drives weren't all that fast after all... should I have gone a different route? But it doesn't make sence to me. Let's see, an 8GB P2 card fits 20min of 24PN 720p so:
8000MB / 20min = 400MB
400MB / 60sec = 66.6`MBps
That would mean that i would ony be able to preview two streams oh HD at the same time, and I'd be running 13.3MB over peak performance? That blows...
but when streaming three of them off a SINGLE 7200.10 with no FXs Vegas seemed very close to real-time preview... ?!?!? Are my eyes THAT slow?
" Programs like HT Tune report the average transfer rate of Seagate 7200.10 drives in RAID0 to be around 120MB/s.
While PCI does allow for a peak transfer rate of 133MB/s it is a shared bus. Meaning any PCI network controller, sound controllers and various other devices that use the bus must also share the 133MB/s bandwidth. So it is unlikely there would be 120MB/s of bandwidth to spare.
Because each PCI Express 1x slot has its own lane is has 500MB/s dedicated to what ever device is plugged into the slot. This means there is loads of spare bandwidth and a single slot can easily support more than 2 drives if need be!
PCI Express comes in a few different modes
PCI Express 1x 250 [500 both ways]* MB/s
PCI Express 2x 500 [1000 both ways]* MB/s
PCI Express 4x 1000 [2000 both ways]* MB/s
PCI Express 8x 2000 [4000 both ways]* MB/s
PCI Express 16x 4000 [8000 both ways]* MB/s "
Wow... only 120MB/s? it sounds slow, did I mess up... maybe these drives weren't all that fast after all... should I have gone a different route? But it doesn't make sence to me. Let's see, an 8GB P2 card fits 20min of 24PN 720p so:
8000MB / 20min = 400MB
400MB / 60sec = 66.6`MBps
That would mean that i would ony be able to preview two streams oh HD at the same time, and I'd be running 13.3MB over peak performance? That blows...
but when streaming three of them off a SINGLE 7200.10 with no FXs Vegas seemed very close to real-time preview... ?!?!? Are my eyes THAT slow?
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