"Your answer is incorrect and makes no sense."
I disagree entirely.
" Look up "RocketRaid 622" which plugs into a PCIe x1 and provides two SATA connections."
BZZZT wrong answer again. The 622 has 2 EXTERNAL ESATA PORTS.
"Secondly, you mention some "chipset" that supposedly only allows one hard drive to function with this motherboard."
I did not say that. The Power Connections are not there for 4 drives.
"This is obviously incorrect as this machine (Inspiron 3650) is advertised with either one 3.5 inch or two 2.5 drives. Why the "or" in the advertisement makes no sense"
It makes perfect sense based on maximum power AND the number of hard drive power connections.
You are ignoring the pictures of the inside.
"In addition, having built computers for over 30 years, I have never heard of any "chipset" that regulates or limits the number of hard drives which can be attached to a motherboard."
Intel Chipsets ICH has been limited to 4 or 6 SATA and with the addition of SATA 3 only 2 drives are that speed the other drives either 2 or 4 are SATA 2. For non server and workstation models the number of drive connectors is limited to 4 and INTEL RAID is usually not supported in BIOS. The Bandwidth for several chipsets limit SATA3 to port 0 and port 1 with port 2 and 3 limited to SATA2 speed and RAID 5 not supported and sometimes no raid whatsoever supported.
"If you would be so kind as to name that chipset - I would be most interested."
You have not been watching INTEL, AMD, NVIDIA chipsets for 30 years. There are too many to mention. In the case of the 3650 there are 4 physical ports and RAID 5 is not supported AND only 2 of them are SATA 3. Z170, H170, H110, B170, Q150, Q170 - What is the Difference?
INTEL CHIPSET Features Z170 H170 H110
Intel Smart Sound Technology Yes Yes No
Intel RST12 for SATA/PCI-E RAID Yes Yes No
Intel Smart Response Technology Yes Yes No
"Lastly - All functionality related to RAID is contained on the expansion card and the "communication bus" and the BIOS only sees the RAID array as one drive."
The card operating is not the only issue. UEFI prevents mass storage drivers from loading in windows 8, 8.1, and 10 unless there is a CERTIFICATE IN BIOS for said card.
"So, I don't see why a PCIe RAID card wouldn't work perfectly with this Inspiron 3650."
Mass Storage cards will not work with SECURE BOOT UEFI bios nor will they be seen.
Lastly the PCI-E version matters. PCI-E 3.0 or 3.1 bus will NOT downclock to 1.0 or 2.0
UEFI allows booting from hard drives larger than 2 TB. Legacy BIOS systems use the Master Boot Record (MBR) hard drive format
, which limits a boot drive to a maximum capacity of 2 TB. While this limitation was not considered an issue years ago, hard drive capacities in the terabytes are common in today’s enterprise environments.
With UEFI BIOS boot the issue of security becomes important.
UEFI includes a Secure Boot function to protect against unauthorized
operating systems and malware rootkit attacks, ensuring that only authenticated code can start on the system.
Secure Boot UEFI uses Microsoft keys and certificates to verify the following:
UEFI drivers loaded from PCIe cards/Storage Controllers
Drivers loaded from mass storage devices
Pre boot UEFI shell applications including firmware updates
Operating system UEFI bootloaders
If a signature verification fails or there is no certificate for a card in BIOS, the process halts and the associated device will not be available for use. The system BIOS ROM carries the Certifcates for
Microsoft ® Windows ® Production Key, UBUNTU Linux®, REDHAT Enterprise Linux®.