So... there may be some obvious reason why they are not popular, but the H240 seems to ridiculously cheap compared to LSI/Broadcom SAS3008 based cards although they have similar specs.
Specwise there isn't that much to say, SAS3, two ports (although they appear to be SFF8087 rather than SFF8643) meaning 8 drives (without expander), PCIe 3, is a HBA by default but also supports cacheless RAID. Some of the posts here on the forum, suggests that you do not need to have a HPE server to use it (checkout the links below).
Here is a link that is nice for us europeans (at least a little while longer anyway) at 30 GBP with cheap shipping, I have seen others that are not much more expensive:
For the non-europeans here is another link at 34 USD that appears to do free shipping (probably US only):
Here are some other threads on the controller:
The firmware (dated 2019) also appears to be available without a support contract:
support.hpe.com
Of course I have no idea about expander support (meaning if they will support LSI expanders and such), and likewise whether firmware updates can be applied without having an HPE server, but I have ordered some and will probably test the latter.
Specwise there isn't that much to say, SAS3, two ports (although they appear to be SFF8087 rather than SFF8643) meaning 8 drives (without expander), PCIe 3, is a HBA by default but also supports cacheless RAID. Some of the posts here on the forum, suggests that you do not need to have a HPE server to use it (checkout the links below).
Here is a link that is nice for us europeans (at least a little while longer anyway) at 30 GBP with cheap shipping, I have seen others that are not much more expensive:
HP+H240+HBA+Smart+Host+Bus+Adapter+-+726907-B21 for sale online | eBay
Find many great new & used options and get the best deals for HP+H240+HBA+Smart+Host+Bus+Adapter+-+726907-B21 at the best online prices at eBay! Free shipping for many products!
www.ebay.com
For the non-europeans here is another link at 34 USD that appears to do free shipping (probably US only):

726907-B21 779134-001 750053-001 HP H240 12GB 2-PORTS INT HBA W/ BOTH BRACKET 657379385247 | eBay
PRODUCT TYPE HBA. NUMBER OF PORTS 2. Helpful Links.
www.ebay.com
Here are some other threads on the controller:
The firmware (dated 2019) also appears to be available without a support contract:
HPE Support Center
Of course I have no idea about expander support (meaning if they will support LSI expanders and such), and likewise whether firmware updates can be applied without having an HPE server, but I have ordered some and will probably test the latter.
Last edited: