A Xilinx Kintex 7 board on AliExpress? - Page 1
Forum section: electronics / general

author: hamster_nz
author_rank: Super Contributor
timestamp: August 05, 2019, 10:47:08 pm
content: Not often you see a Kintex 7 XC7K420T dev board for under US$170https://www.aliexpress.com/item/32907109444.htmlThese really must have "fallen off a truck", or somebody got dumped a lot of old parts(Yes, I do have the required license for Vivado that is needed to use this, no I am not buying one)

author: SiliconWizard
author_rank: Super Contributor
timestamp: August 05, 2019, 11:02:08 pm
content: Uh. Sounds... incredible...You know how much a XC7K420T itself costs I suppose...https://www.digikey.com/product-detail/en/xilinx-inc/XC7K420T-1FFG901C/122-1839-ND/3911025So yeah maybe those are fake boards, or stolen, or just some stock gotten from a company that has gone bankrupt...

author: Mr. Scram
author_rank: Super Contributor
timestamp: August 05, 2019, 11:07:49 pm
content: I've bought FPGA boards from Aliexpress and possibly even this seller. They seemed to roll their own boards.

author: hamster_nz
author_rank: Super Contributor
timestamp: August 05, 2019, 11:09:21 pm
content: Quote from: SiliconWizard on August 05, 2019, 11:02:08 pmBut those slots for SFP optics are calling me... must resist.

author: SiliconWizard
author_rank: Super Contributor
timestamp: August 05, 2019, 11:13:30 pm
content: Well if the boards are in working order and the FPGA is genuine, that would be hard to resist indeed...

author: Mr. Scram
author_rank: Super Contributor
timestamp: August 05, 2019, 11:25:14 pm
content: Note that the boards I bought came with more mundane FPGAs. I'm trying to find out whether that was this seller.

author: KE5FX
author_rank: Super Contributor
timestamp: August 06, 2019, 12:35:40 am
content: Quote from: SiliconWizard on August 05, 2019, 11:13:30 pmIf they're cloning midrange FPGAs these days, I'm impressed. Even a ghost-shift production run wouldn't be trivial to pull off under Xilinx's nose.But how does the Vivado license work?XC7325T isn't supported under Webpack, much less XC7420T. Those are kilobuck+ parts.

author: AndreZheng
author_rank: Contributor
timestamp: August 06, 2019, 09:34:33 am
content: This kind of high end FPGAs are teared off parts from boards like: communication board, bitcoin miner machine etc. And the BGA balls are re-soldered. The price for XC7K325T-1FGG676C chip near 100$. And after adding those SFP interfaces, how could this board be only taking 170$?! Incredible!

author: NivagSwerdna
author_rank: Super Contributor
timestamp: August 06, 2019, 09:58:03 am
content: I quite like the look of this... what would I need to adapt the SPF+ to wired ethernet?

author: Mr. Scram
author_rank: Super Contributor
timestamp: August 06, 2019, 10:15:26 am
content: Quote from: NivagSwerdna on August 06, 2019, 09:58:03 amA switch with SPF would probably work.

author: ali_asadzadeh
author_rank: Super Contributor
timestamp: August 06, 2019, 10:51:16 am
content: These Prices for FPGA is somehow normal in china! do not worry that much

author: Scrts
author_rank: Frequent Contributor
timestamp: August 06, 2019, 12:50:01 pm
content: I guess there's no RAM? Extremely limited board IMHO... You can only rely on internal BRAM for memory and that's it.

author: oPossum
author_rank: Super Contributor
timestamp: August 06, 2019, 12:53:02 pm
content: This version has 2 DRAM SODIMMshttps://www.aliexpress.com/item/32956526454.html?spm=a2g1y.12024536.productList_35413432.pic_2

author: Scrts
author_rank: Frequent Contributor
timestamp: August 06, 2019, 01:11:36 pm
content: That's better. And the expansion port seems to be better as well

author: asmi
author_rank: Super Contributor
timestamp: August 06, 2019, 01:13:15 pm
content: Quote from: KE5FX on August 06, 2019, 12:35:40 amIf you buy a K7 devboard from Xilinx or Digilent, they will give you a voucher for Vivado, which is device-limited to whatever device that is on a board (and includes a year of free updates). This might be a cheaper option if you want to work with such a device. I'm considering buying a Genesys 2 board just for that purpose as it's the cheapest way to obtain this license for K325T device as shelling out 3k$ for a full Vivado license is way beyond my hobby's budget.

author: asmi
author_rank: Super Contributor
timestamp: August 06, 2019, 01:59:14 pm
content: Quote from: Mr. Scram on August 06, 2019, 10:15:26 amSFP only supports speeds up to 2.5G, if you want 10G - you will need SFP+. 10G switches are much more expensive, and 1G via fiber optic doesn't make much sense as you can get the same speed with any Gigabit Ethernet PHY and CAT5 cable. Though fiber does have range advantage if that's something you need.

author: SiliconWizard
author_rank: Super Contributor
timestamp: August 06, 2019, 03:19:59 pm
content: Quote from: ali_asadzadeh on August 06, 2019, 10:51:16 amUh huh. I'm sure China has nice deals for Xilinx parts, but we're talking about a part that is sold at ~2500USD per 1 in western countries. Is Xilinx this generous with China?

author: SiliconWizard
author_rank: Super Contributor
timestamp: August 06, 2019, 03:21:27 pm
content: Quote from: asmi on August 06, 2019, 01:13:15 pmYes, the board is still $999...And doesn't the Aliexpress board you mentioned have a XC7K420T and not a K325T?

author: Mr. Scram
author_rank: Super Contributor
timestamp: August 06, 2019, 03:26:17 pm
content: "Don't worry, I wrote 12,9USD on the packing box."

author: asmi
author_rank: Super Contributor
timestamp: August 06, 2019, 04:23:03 pm
content: Quote from: SiliconWizard on August 06, 2019, 03:21:27 pmYes, but it's still cheaper than 3k$ just for a license...Quote from: SiliconWizard on August 06, 2019, 03:21:27 pmI didn't mention it. I would love to try that one out, but it's way beyond what I can afford to spend on a hobby. It's very expensive as it is.

author: SiliconWizard
author_rank: Super Contributor
timestamp: August 06, 2019, 04:37:18 pm
content: Quote from: asmi on August 06, 2019, 04:23:03 pmThat's for sure...Quote from: asmi on August 06, 2019, 04:23:03 pmOK. Think I got confused at some point in the thread because it went a bit off-topic.Thought you were mentioning buying the Digilent board as an option to get a cheaper license to be able to use the Aliexpress board...

author: asmi
author_rank: Super Contributor
timestamp: August 06, 2019, 07:34:16 pm
content: I only recently realized just how much faster Kintex fabric is compared to Artix. HDL that closes timing at only 185 MHz on Artix, is closing at 280 MHz on Kintex (both are -2 speed grade)!

author: colorado.rob
author_rank: Frequent Contributor
timestamp: August 06, 2019, 08:31:50 pm
content: I'm seriously considering giving the $350 board a go. You can get 10GBasetT Ethernet SFP+ Transceiver modules for $50. And 1GBaseT SFP goes for under $20.But having to shell out $3k for a Vivado license is going to be a deal breaker for me.

author: Jope
author_rank: Regular Contributor
timestamp: August 06, 2019, 11:01:10 pm
content: Quote from: colorado.rob on August 06, 2019, 08:31:50 pmScroll down on the Aliexpress website and look at the list of supplied files...

author: asmi
author_rank: Super Contributor
timestamp: August 06, 2019, 11:38:02 pm
content: Quote from: colorado.rob on August 06, 2019, 08:31:50 pmUnless you already have an SFP+-capable switch, you will need to buy something to connect the fiber to. And the cheapest option will probably be to buy a second board

author: langwadt
author_rank: Super Contributor
timestamp: August 06, 2019, 11:54:50 pm
content: Quote from: Jope on August 06, 2019, 11:01:10 pmins't the license tied to MAC address or HDD id? not that either is a big hurdle to overcome

author: langwadt
author_rank: Super Contributor
timestamp: August 06, 2019, 11:58:33 pm
content: Quote from: Mr. Scram on August 05, 2019, 11:07:49 pmat the price I would expect it to be boards they got for free as scrap from someone who had them made for specificproject that then got cancelled

author: asmi
author_rank: Super Contributor
timestamp: August 07, 2019, 12:53:08 am
content: Quote from: langwadt on August 06, 2019, 11:58:33 pmI personally don't really care how they came about, as long as they work. These are devboards, so they aren't to be used for any production system anyway.

author: colorado.rob
author_rank: Frequent Contributor
timestamp: August 07, 2019, 01:03:45 am
content: Quote from: asmi on August 06, 2019, 11:38:02 pmNot at all. $20 from Amazon:SFP to RJ45 Copper Module - 1000BASE-T Mini-GBIC Gigabit Transceiver/url]

author: asmi
author_rank: Super Contributor
timestamp: August 07, 2019, 01:20:57 am
content: Quote from: colorado.rob on August 07, 2019, 01:03:45 amThis is 1G SFP module, I'm talking about 10G SFP+.

author: colorado.rob
author_rank: Frequent Contributor
timestamp: August 07, 2019, 01:27:55 am
content: Quote from: asmi on August 07, 2019, 01:20:57 amI don't need that at all -- I just need to connect it to my network.

author: asmi
author_rank: Super Contributor
timestamp: August 07, 2019, 01:46:40 am
content: Quote from: colorado.rob on August 07, 2019, 01:27:55 amWhat's the point then? You can connect to 1G network using regular cat 5 cable and ethernet PHY, which is present on a lot of FPGA boards. You don't even need the speed of Kintex for that - Artix will be just fine.

author: hamster_nz
author_rank: Super Contributor
timestamp: August 07, 2019, 01:50:06 am
content: Glances at parts salvaged from decommissioned gearThese are for 8Gb/s Fibrechannel... would need to actually open a box to find 10Gb/s ones.

author: andersm
author_rank: Super Contributor
timestamp: August 07, 2019, 06:40:08 am
content: Quote from: asmi on August 06, 2019, 11:38:02 pmMikroTik recently-ish released adesktop switch with four SFP+ ports, with a suggested price of $150. 10Gig SFP+ DAC copper cables cost about$20, depending on length.

author: colorado.rob
author_rank: Frequent Contributor
timestamp: August 07, 2019, 05:25:25 pm
content: Quote from: asmi on August 07, 2019, 01:46:40 amBecause I want play around with Kintex performance for things other than networking? The $350 board has SMA connectors, PCIe, and memory that I am interested in using, and that I do not see elsewhere at that price point.

author: asmi
author_rank: Super Contributor
timestamp: August 07, 2019, 06:34:12 pm
content: Quote from: colorado.rob on August 07, 2019, 05:25:25 pmFair enough. With all discussion above about SFP+ I assumed that you're after networking.

author: Canis Dirus Leidy
author_rank: Regular Contributor
timestamp: September 11, 2019, 05:22:24 am
content: Quote from: SiliconWizard on August 05, 2019, 11:02:08 pmWell, according to Russian Anonymous, it's usually works:https://2ch.hk/ra/res/316943.html#346384https://2ch.hk/ra/res/316943.html#377813

author: olkipukki
author_rank: Frequent Contributor
timestamp: September 11, 2019, 11:31:31 am
content: Quote from: hamster_nz on August 05, 2019, 10:47:08 pmHow much would cost UltraScale then that the seller mentioned in the listing?!

author: asmi
author_rank: Super Contributor
timestamp: September 11, 2019, 01:28:24 pm
content: Quote from: olkipukki on September 11, 2019, 11:31:31 amYou can send the seller a message and askI ended up buying Genesys 2 board from Digilent. It's a nice board, and FPGA is fuuugee (considering I only worked with up to A50 before) and faaaast!Working on some HDL for DisplayPort right now, also designing an FMC board with all cool hi speed stuff (SATA, SFP+, etc.), as its FMC have 10 transceivers bonded out!

author: SiliconWizard
author_rank: Super Contributor
timestamp: September 11, 2019, 02:51:04 pm
content: Quote from: asmi on September 11, 2019, 01:28:24 pmDamn this thing is big. Now this is an FPGA for grown-ups!

author: asmi
author_rank: Super Contributor
timestamp: September 11, 2019, 03:33:42 pm
content: Quote from: SiliconWizard on September 11, 2019, 02:51:04 pmOh yeah, but more importantly I now have a license to use XC7K325T in any package on any design I wantThe FPGA on this board is -2 speed grade, which means it supports up to 1866 MT/s DDR3 (it's got a pair of 256Mx16 memory chips which can run up to 933 MHz, though so far I only ran it at 900 MHz/1800 MT/s due to the way clocking is implemented on a board) , also its MGTs can go up to 10.3125 GBit/s, so they can directly talk to 10G SFP+ transceivers, not to mention it's possible to implement a PCIE 3.0 x8 via fabric!One issue I noticed with the board is they use Realtek Ethernet PHY, which apparently is not supported by lwIP nor AXI Ethernet driver provided by XilinxStill trying to figure this part out. Another kind of annoyance is their choice to connect system clock to the MIG's bank as this somewhat limits the kind of clocks you can get if you do use MIG. I'd really like another clock connected elsewhere. Though technically it should be possible to use MGT's 135 MHz clock inside the fabric, but I didn't try this yet.But overall I'm reasonably pleased with a set of peripherals present on a board. Among others are: SD card (sadly it's 3.3 V only, so no UHS), USB 2.0 ULPI PHY, audio codec (that's rather unusual), HDMI in/out, full four lane DisplayPort in/out (with 10G transceivers it's technically possible to implement up to DP 2.0 UHBR 10 - total 40 Gbit/s - if I could only get my hands on specification!), small OLED display. And the best "peripheral" is of course the fully bonded out FMC connector with 10 MGTs!One odd peripheral for such hi-performance FPGA is VGA portOne thing I wish it would have is a couple FPGA pins (one CC, another regular IO) broken out to SMA connectors as this is a great debugging tool.

author: SiliconWizard
author_rank: Super Contributor
timestamp: September 11, 2019, 08:32:47 pm
content: Still a toy compared to a Virtex-7 though!

author: asmi
author_rank: Super Contributor
timestamp: September 11, 2019, 09:01:12 pm
content: Quote from: SiliconWizard on September 11, 2019, 08:32:47 pmThat's probably true, but for now K7 is more than enough for my needs. Besides, K7 chips are at least theoretically affordable, while V7 are totally out of my league. And given the choice, I'd rather go for Kintex Ultrascale/US+, than for V7, as they have much faster IO and support more modern IO standards like MIPI or DDR4.

author: mac.6
author_rank: Regular Contributor
timestamp: September 12, 2019, 08:38:59 am
content: My biggest toy is a dev board for SoC validation with a XC7V2000.Sadly the project got cancelled and the board is gathering dust since...

author: colorado.rob
author_rank: Frequent Contributor
timestamp: October 17, 2019, 02:45:36 am
content: I ordered one of theXC7K420T boards with QSFP and DDR3for about 340 USD along with a Xilinx programmer for $8 from the AliExpress seller. They both showed up in the mail today. Oddly, the vendor shipped a power adapter in a separate package -- it came with a European plug and I'm in the US. Not that it matters. I'm powering it from a bench supply. And I have adapters. The PS claims it will work at 120V/60Hz.The board is much larger than I expected. I don't know why, but I thought it looked smaller on the web page. There is a large 5x25 pin connector (apparently AVX/ELCO 7200 series 2mm pitch) at the top with 32 GPIO and 16 differential pairs, 8 in, 8 out, exposed. There are 16 LEDs, 3 tactile switches, and a tiny 4-way DIP switch. Button placement is a bit odd, making it easy to press the wrong button when using them for input.The vendor was very helpful before the sale, sending schematics and code upon request. Shipping was a bit slow. It took two weeks for the board to ship, and two more weeks to arrive. I placed the order Sept 18 and it was accepted in the mail in China on Oct 3.I am running through various tests right now and so far it seems OK.

author: RoGeorge
author_rank: Super Contributor
timestamp: October 31, 2019, 12:24:48 pm
content: Looks great!Just curious, what kind of projects do you have that require such a big FPGA?

author: colorado.rob
author_rank: Frequent Contributor
timestamp: November 09, 2019, 02:10:33 am
content: Quote from: RoGeorge on October 31, 2019, 12:24:48 pmMostly just learning. I don't *need* anything. I wanted a board with many of the features that this one had, such as MGTs brought out via SMA, SFP, DDR3 and PCIe just to learn this stuff.I am currently building up the Vivado board files for this thing so I can easily construct designs in Vivado IP Integrator. At this point I have the IOs, clocks, SFPs and DDR3 banks done. I have 1000BaseX and 1000BaseT SGMII SFP modules to test with, and I just picked up some cheap QSFP modules to test with. I've never created board files before (or used the MIG) so this has been rather challenging. I currently have "echo server" running on MicroBlaze with one of the DDR3 banks.I guess I should post the board files up on Github soon so anyone else that is interested can play along.This weekend I am going to try to get PetaLinux running on it. I'm probably being a bit ambitious...In the near future I may end up making a board to connect to the IO expansion header for HDMI, USB and microSD.Longer term, I'd really like to get the SATA port working. It looks like there are a few open SATA implementations I can try out. I am clueless as to what it would take to get that working under Linux. I have no idea whether any would work with an existing kernel driver, or could be modified to work with an existing driver, or if I'd have to make my own kernel driver.That's probably a ways down the road as I imaging getting PCIe running will be a bit challenging.Update: Linux is running using buildroot to build the image. Ethernet isn't working under Linux yet. Need to get that working, then see what it takes to boot Linux from QSPI. I've currently got the QSPI configuring the board as an echo server on power-up.

author: colorado.rob
author_rank: Frequent Contributor
timestamp: November 11, 2019, 12:42:06 pm
content: I just saw that the board vendor is selling a version of the board I purchased for around $215. These are boards where only one of the DDR3 banks is working. This looks like a great deal if you don't need 2 banks of RAM.https://www.aliexpress.com/item/4000316057061.htmlEdit: updated price and added link.

author: colorado.rob
author_rank: Frequent Contributor
timestamp: November 11, 2019, 05:12:33 pm
content: Anyone here with buildroot experience? I am trying to get buildroot to automatically initialize the Ethernet port for the MicroBlaze system. I haveCode:BR2_SYSTEM_DHCP="eth0"set in the build, but I never get the appropriate stanza written to /etc/networking/interfaces. There are so many existing hardware configs that use this that I assume that it works and that I am just missing something.If I manually add the required lines to "interfaces", I can ifup eth0 and get an IP address. (On the second attempt, but that's for another time.)What's the right way to automagically bring up an Ethernet interface using buildroot?

author: mark03
author_rank: Frequent Contributor
timestamp: November 14, 2019, 10:50:52 pm
content: For those that bought the XC7K420T board, did you already have a Vivado license? Or do they come with something you can use to make the webpack installation work? I see the only webpack-supported Kintex-7 part is the XC7K160T.

author: colorado.rob
author_rank: Frequent Contributor
timestamp: November 15, 2019, 04:55:11 am
content: Your question has been answered in this thread. You can find a way to make it work.

author: KaneTW
author_rank: Frequent Contributor
timestamp: November 15, 2019, 06:45:46 am
content: Quote from: SiliconWizard on August 06, 2019, 03:19:59 pmFPGA pricing at distributors is absurd. From what I can tell the markup is easily 10x, if not higher [compared to buying in volume].

author: colorado.rob
author_rank: Frequent Contributor
timestamp: November 24, 2019, 11:07:54 pm
content: For any of those interested, I have published the board support files I have developed so far. There are Vivado board files, which includes all clocks, both DDR3 banks, both SFP+ connectors, QSPI flash, I2C EEPROM, and GPIOs. There is also a master XDC constraints file, UCF files for MIG, and MIG project files for both DDR3 banks.There is still work left to be done on the PCIe, QSFP and SATA interfaces. (If anyone knows of an open source SATA project with Linux support, please let me know.)https://github.com/rriggs/kintex-7-hpc-v2-board-filesI have tested this by having Linux boot on a Microblaze (using buildroot), tested with both DDR3 banks, and using a 1000Base-X SFP adapter. Network support is still dodgy, but I think that's because either the Xilinx Ethernet IP lacks decent support for SFP adapters or their device-tree support does.The schematics are also uploaded to this repo.There is a second QSPI flash chip on the board labelled U30 which is not documented in the schematics. The vendor just responded with the connection information. I'll update the board files and master constraints file with this information soon.I am fairly new to FPGAs so I'm sure there are a lot of things that can be improved. I am trying to learn, so any feedback would be greatly appreciated.I plan to upload a sample MicroBlaze Linux project with buildroot configuration to Github next. I'd like to get the project in a more stable state first.

author: lawrence11
author_rank: Frequent Contributor
timestamp: November 25, 2019, 03:52:30 am
content: So what motivates the price for these things?Does it take like 1000 chips to get one right?Does the "die" cost like 100 million?

author: mac.6
author_rank: Regular Contributor
timestamp: November 25, 2019, 08:29:57 am
content: extremely expensive R&D, expensive support and expensive manufacturing cost multiplied by margin.You can't really amortize that on a bazillion of chips sold like processor or ram.

author: Rasz
author_rank: Super Contributor
timestamp: November 27, 2019, 02:47:43 pm
content: Quote from: langwadt on August 06, 2019, 11:58:33 pmMerely going by the size of Robomasters China has >100 Universities pumping EEs. Someone has to supply all the devel tools, all financed by the governmenthttps://www.forbes.com/sites/willyshih/2019/11/22/chinas-latest-development-fund-and-the-impact-on-american-companies/

author: ciclonite
author_rank: Contributor
timestamp: November 24, 2020, 02:09:07 pm
content: Hey, Rob! how are you? Any news with the board? I want to buy the v3 version for black fridayThe board worth the money?Thanks.

author: gpgpu999
author_rank: Newbie
timestamp: January 29, 2023, 12:44:01 pm
content: If anyone is interested, I'm selling some of these Kintex 7 dev boards that I bought from AliExpress. I tested one but otherwise haven't used them at all.https://www.ebay.co.uk/itm/144920938728I've just listed one but I have a total of ten if anyone would like to take them off my hands!