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I'm interested in using some high-performance FPGA development boards, but it seems like most of the high-end, modern options from both Xilinx (Digilent) and Altera (Terasic) seem to be PCIe-based boards. I almost exclusively do development on a laptop, where I don't have a PCIe slot.

Is there a reason that there aren't high-performance boards available as standalone, USB devices? Is this the standard way that the devices are used in practice? Do you have recommendations for how I can integrate a top-of-the-line device (preferably Xilinx) into my workflow?

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  • \$\begingroup\$ You might look for old bitcoin mining fpga rigs \$\endgroup\$ – Some Hardware Guy Apr 30 '15 at 17:55
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They tend to have PCIe form factors because it is a modern bus used in many high speed applications - I'm currently developing a PCIe Gen3x8 application around an Altera one.

But if you don't need the PCIe capability, it is possible to use these boards stand-alone. They tend to have external power supplies which can be used if not connected to a motherboard. You can also pretty easily remove the PCIe bracket from them and they can then be mounted horizontally on something.

If you do want PCIe, but only have a laptop, then this is possible too. You can get an Express Card to PCIe adapter (I've used the one from OneStopSystems). Be aware though, these are only single lane Gen1. In my current project, I've tried connecting my Gen3x8 design via one of these backplanes to a laptop and it correctly negotiates down to Gen1x1 and works perfectly (albeit considerably slower).

You can get development boards for USB 3.0 which are standalone - I think there is a cypress one for example. But USB, even 3.0, is generally much slower that the capabilities of the high end FPGAs - in fact many of the FPGAs can go faster than USB3 or PCIe3 can handle.

The other distinct advantage of PCIe over other buses, is most of the high end FPGAs already have CML transceivers built in to them, which means they can be interfaced directly to PCIe signals without the need for external ICs. Ethernet and USB on the other hand tend to require external PHY chips, so result in more complex (and expensive) designs.

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  • \$\begingroup\$ Thanks for the tips @Tom. I wasn't aware that some of the boards could be operated independent from the PCIe bus, and could be used stand-alone. I'll consider using the adapters as you mention as well. \$\endgroup\$ – Sam May 1 '15 at 16:17
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There was a small market for PCMCIA based FPGA addon cards, but PCMCIA is dead. I can't find any references if these cards got updated to Express Card.

If you are seeking for FPGA boards with USB 3.0 support there are some exemplars like this: https://www.opalkelly.com/products/xem7350/

If you want to do "high-performance computing" with FPGAs you will always need a high-speed link. And that's PCIe. USB 3.0 is not fast enough. Writing USB drivers is also quite complicated.

You can use most FPGA prototyping boards as a standalone board e.g. (Xilinx VC707) and connect it with 2 USB cables to a laptop (1 = JTAG/Programming/Debugging; 2 = USB-UART-Bridge). If you need faster data exchange, use Gigabit Ethernet :)

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Buy an express card to PCIE adapter. The express card slot in any modern laptop has a 1x PCIE bus. All you need is the right adapter to connect the board.

Usually they are made for using an external video card, but the type of device shouldnt matter.

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