Yes, a PCIe bus have a transfer rate of 250 MB/s - overhead
PCIe 2.0 x2 can theoretically transfer 1000 MB/s, in real you get ~720 MB/s
Overhead is around 25%
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Can someone recommend a good PCI adapter for my SSD?
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Yes, a PCIe bus have a transfer rate of 250 MB/s - overhead
PCIe 2.0 x2 can theoretically transfer 1000 MB/s, in real you get ~720 MB/s
Overhead is around 25%
I'm an idiot
Some cards has a x2 interface. With this cards you can get around 400 MB/s, but the most card having some compatibility issues.
I will test my sonnet tempo SSD inside a PCIe 1.0 slot and report you, but now I must go to sleep^^
Some cards has a x2 interface. With this cards you can get around 400 MB/s, but the most card having some compatibility issues.
I will test my sonnet tempo SSD inside a PCIe 1.0 slot and report you, but now I must go to sleep^^
Ok I was right, I'm not a complete idiot^^
The most x2 cards having connectors for 2 SSDs and it look like x2 cards are using only 1 lane for every SSD.
Here is a Sonnet Tempo SSD in a PCIe 1.0 slot (in a PCIe 2.0 slot I get around 500 MB/s)
The most x2 cards having connectors for 2 SSDs and it look like x2 cards are using only 1 lane for every SSD.
Here is a Sonnet Tempo SSD in a PCIe 1.0 slot (in a PCIe 2.0 slot I get around 500 MB/s)
Ah, I see. Thanks for testing that for me. I guess there's no point in getting an adapter, then.
All of these references to MB/sec miss the fact that even on a SATA 1.5Gbps link the SSD will have far higher IOps than any spinner on random IOs.
If you're loading apps and other tasks that access scattered parts of the disk, there will be little difference in practical terms between simple MOBO SATA and the fastest PCIe SATA card. The biggest win is getting rid of the head movement delays on the spinner - eliminating head delays of tens of milliseconds is by far more important than shaving a few microseconds off the transfer time.
In other words, delete the BlackMagic app and don't worry about raw sequential bandwidth.
If you're loading apps and other tasks that access scattered parts of the disk, there will be little difference in practical terms between simple MOBO SATA and the fastest PCIe SATA card. The biggest win is getting rid of the head movement delays on the spinner - eliminating head delays of tens of milliseconds is by far more important than shaving a few microseconds off the transfer time.
In other words, delete the BlackMagic app and don't worry about raw sequential bandwidth.
One look at Blackmagic's Disk Speed Test should give you a pretty good clue what that app is about. It has a purpose.
It was the first app a few years back that highlighted an issue I had noticed with an OWC SSD in a 5.1 MP SATA bay. Other benchmarking apps had the SSD at 270+ MB/s, but Blackmagic's DST only showed me 50-60 MB/s on the same SSD. <--- the slower speeds were closer to what I was experiencing during editing.