eSATA SxS Card Reader for Desktops

[Steve Gibbons]

Is anyone aware of an eSATA attached ExpressCard (SxS) reader for desktop PCs?

I know of this product that was just released:

Sonnet - Qio: Professional Universal Media Reader/Writer Plus Four eSATA Ports

...but that includes a controller card. I am looking for a reader that attaches directly to an existing eSATA cable plugged into the integrated controller on the motherboard.

Thx

[George Kroonder]

Those look good. Order either one and store the PCIe or ExpressCard if you want to use your exising eSATA connection. It's not like a PCIe card will add a significant amount to it. The ExpressCard may even prove usefull at times you want to take it somewhere and connect it to a notebook.

Just accept that 'solutions' come as a complete bundle.

George/

[Brooks Graham]

I doubt you'll ever find an eSATA-to-ExpressCard device.

Why? Because ExpressCard is closer to being a PCIe card than you might have realized. On the connector that plugs into your computer, an ExpressCard device can use either of two interfaces: USB or PCI Express.

If the ExpressCard device uses USB (like our KxR/MxR/MxM/XxX adapters) then there's really no difference over plugging something into USB. The idea of making an adapter that converts eSATA (a storage-only interface) into USB (a Universal Serial Bus) - while possible - would be expensive, require messy device drivers and give no benefit over just using USB directly.

If the ExpressCard uses its PCIe interface, it is actually a 1-lane PCIe card the same as if you plugged a PCIe card onto your motherboard. The Sony uses the PCIe interface on their SxS cards which is why writing to and reading from them is substantially faster than USB. (and one of the reasons they're more expensive than USB solutions) So SxS cards are actually 1-lane PCIe cards.

Now take that Sonnet device, it should be clear now why it needs a PCIe card to be plugged into your motherboard - that card is extending the PCIe bus from the motherboard up into their device and making it available to their ExpressCard slots. (BTW, this might help to explain why Sony's SxS USB adapter is so "expensive". In that device, they have to have enough of an independent computer system inside there to create a PCIe bus for the SxS cards, then convert that to USB. Way, way more complex than one of those throw-away flash card USB adapters. So I guess Sony isn't ripping us off after all.)

So what would an eSATA to ExpressCard device need to do? Convert eSATA (a block storage interface) to PCIe. You'd be asking for a device that would let you plug, for instance, an ATI Radeon HD 4870 graphics card into an eSATA connector. While I suppose everything's possible, it's not likely and would be ridiculously expensive - not to mention nearly impossible to implement from a driver standpoint.

Sounds to me more like a solution in search of a problem. Just use the PCIe bus.

[George Kroonder]

Yeah, read the Sonnet info wrong; assumed it interfaced via eSATA with the PC, but it is essentially a PCIe extender box which requires a 'proprietary' interface card (PCIe/ExpressCard).

Seems like a good solution though.

George/