What limits the number of controllers inside a single PC? For example, if I do not care about enclosure, power, cooling considerations - and all the other superficial facts - what are the negotiable and un-negotiable limits on just how many drives may be attached to a single motherboard?

I was considering posting under the "Maximum drives limit attachable to a single Motherboard", but my questions is really about how to squeeze some cheap controllers and commodity SATA drives and not novel-enterprise hardware, because of simply the cost factors.

For example, I would even go as far as 1 USB CD, 4 IDE HDD and five SATA HDD as long as the USB CD boots - but would it work?

What limits this besides the superficial and the available expansion slots on the motherboard, the OS used, and what else? And no - no USB or FireWire or other expansions but drives attached directly to the system bus. SCSI, SAS or whatever is also enterprise and expensive, what are some of the other options?

How many and how did you manage to make work, please share! Nothing important depends on this for me, but I have a hard time piecing the BIOS, chip-set, IRQ, and all other factors together. Thanks!

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    Well since you think power and cooling are just superficial for whatever it is you're trying to accomplish with this question then the answer is: as many as you can scrounge up and connect to the MOBO. Your MOBO does not have a "Data-Storage" limit, only OS's do. As long as you can keep making the connection to the MOBO then you'll be able to keep adding storage devices to it. – Andrew Dec 17 '14 at 10:51
  • You are saying if I fill all the expansion slots with SATA controllers the BIOS might go crazy but Linux is going to be fine, or the BIOS will be fine as well as any OS? I do not have the money to buy controllers and hard drives to test and see, I only need to know if there is anything in the BIOS, chip set, PC-architecture or anything else which would disallow this.. Thanks for posting! – arch-abit Dec 17 '14 at 11:18
  • @Reeves "whatever it is you're trying to accomplish with this question" On my own time and by my own resources I am trying to build a simulation of a production environment at my current employer, using a single box and a desktop - Semper fidelis! – arch-abit Dec 17 '14 at 12:48
  • My thanks to the moderators for closing this post of mine. I usually try to close my posts or delete them if they are too broad, but in this case the bottom line is as long as there is free expansion on the mobo the number of SATA controllers installed is only limited by OS support to read, and then write and use them. Thanks again! – arch-abit Dec 27 '14 at 5:44

A storage controller as you are describing is a PCI or PCIe device, so the maximum number, type, and firmware behavior of the PCI/e in devices your system will control the maximum number of drives you can use with your system. The other physical limiting factor will be the power supply you'll need to power each drive.

Just a brief look on newegg.com I'm seeing X1 PCIe cards with 4 SATA ports. So assuming your system has 4 PCIe slots and integrated video, you're looking at 16 drives plus whatever ports your motherboard has. I don't know how "port multipliers" work but supposedly you can use them on compatible cards to split one port among 15 drives, splitting the SATA bandwidth amongst them if you wanted to get really crazy.

PCI/e devices hook into the BIOS via an option ROM. On some BIOSes/firmwares you can tell the BIOS/firmware to ignore any or specific option ROMs on boot, you may need to do this with multiple storage cards if problems arise.

Other than that the BIOS/firmware won't care. This is not to say you won't encounter a buggy BIOS or firmware that has issues where it shouldn't. Good luck.

I have a hard time piecing the BIOS, chip-set, IRQ, and all other factors together.

ISA is dead. Setting IRQ jumpers on devices hasn't been relevant on PCs for a long, long time.

The motherboard chipset will have a built-in storage controller into it, or allow access to one on a motherboard, but internally it looks and works like a PCI/PCIe device, so it's nothing you really need to configure other than boot options in the BIOS.

  • Thank you, it's been a long time I had to worry about these things. I run vbox on Linux, and I am running out of storage for Windows installations, obviously they do not ALL run at the same time but the number of virtual machines keep increasing and the snapshot sizes are humongous. I do not anymore try to mount hard drives, they are 2.5" laptop HDD and SSDs, not much heat, I just cram them inside the 32GB TS140 I use. It's a test setup. – arch-abit Dec 17 '14 at 11:51

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