NAS noob in need of help

Found this forum after stumbling accross JDM_WAAAT on YouTube for the NAS Killer 4.0 build. I’m a complete noob when it comes to NAS and am looking for some help.

Backstory - In the past I’ve had a simple WD portable drive plugged into my router which has worked fine for the most part. However, I just had a drive failure which resulted in full data loss, and am now looking at better options which include redundancy.

Starting Point - I currently have an old hand-me-down Dell Optiplex 790 Mini-Tower that I use as an HTPC. My plan is to re-use this (or parts) of it in my NAS build. Specs: i5-2400, 16GB DDR3 RAM, 128GB System SSD, 2TB Hitachi Ultrastar.

I’ve looked a bit at a motherboard upgrade, however, sounds like Dell uses it’s own proprietary motherboard size / mounting points.

My main concerns / questions -

  1. Not super familiar with ZFS / RAID. I’m looking at using FreeNAS. Is it possible to re-use the existing 2TB HDD and have two pools, one 2 2TB the other 2 4TB (or something similar). Or is it best to buy all same size drives and go from there? After a bit of research on ZFS, sounds like for sake of expansion, it’s best to have more “pools” with fewer drives in each (although this has the downsize of decreasing usable space).

  2. Down the road with expansion, the current mobo has only 4 SATA ports (1 SATA 3 and 3 SATA 2). I believe it’s the case, but want to verify. If I run with my 4 SATA drives for now, can I then later add a SAS controller via PCIe and mix SATA + SAS drives?

  3. The mobo (I believe) has just PCIe GEN 1 - 1 16x, 1 4x, 1 1x, and one standard PCI. Will this cause speed issues with a SAS controller like the LSI 9201-8i?

  4. LSI 9201-8i and similar cards look to be PCIe Gen 2 and show 6GB/s, however, PCIe Gen 2 spec is only 500MB/s. Wouldn’t this cause a bottleneck? Am I just completely misunderstanding this?

  5. The stock power supply has only 4 SATA power leads. Is this something where I can just buy power splitters mentioned int he build guide? Or am I kind of SoL for expansion?

Any help on these questions and concerns would be appreciated. Or let me know if it would be better to just scrap the 790 altogether and start a new build from scratch.


The cleanest solution would probably be a NAS Killer 4.0 build and Unraid. Dell boards are fairly proprietary and not easy to tweak. Having said that, you can certainly maximize the utility of the 790MT:

Sandy Bridge should be PCIe 2.0. That’s 500MByte/s per lane, far more than the SAS2 HBA can use (9201-8i is PCIe 2.0 x8). Your case is a bit limiting, but you can get a 3-in-2 cage that can cram three 3.5" drives in your two 5.25" bays. So that’d be 5x 3.5" drives plus an SSD that you can fit anywhere. You may be able reuse the DVD’s SATA port for a drive. To power the drives, pick up a SATA power splitter cable and remove its 3.3v line (the one closest to the “L”), to avoid SATA PWDIS issues.

Unraid gives you a lot more flexibility than ZFS in expansion. If you don’t have a lot of experience managing ZFS, or experience with Linux, I’d recommend giving Unraid a try. There’s a free trial.

If you’re looking for something easy, buy one of the 4.1 combos, strip it out, and put it in a case (with the rest of the parts you need)!