I bought a refurbished Lenovo M720s computer last summer to use as a homelab at my house. I loaded True Nas onto the internal SSD and swapped out the HDD drive that came with it for a 10tb drive. I also threw a 500gb drive in the M.2 slot to use for applications with True Nas.
All has been fine up to now. Recently though I aquired a 8tb HDD for cheap and figured I would throw it into the homelab for some extra storage. There was a extra Sata connector free on the motherboard anyway. I put in the drive and connect it, but then I realize that there is not another Sata power connector I can use for this drive. This computer makes you connect power to the drives from the motherboard and not the power supply.
So I am at a bit of a roadblock. I know I am pushing the capabilities of this little machine, but it seems silly that they give you 3 Sata ports but only 2 power ports for Sata drives. I guess they were probably intending for one of those ports to just be used for a DVD drive.
I went to a local computer store and they were not very helpful. I asked if I could use a splitter for the power port and they said I would fry my board.
Anyone know any solutions to this? I just need a way to power one more HDD. I will link the manual to the computer so it is easier to see what I am looking at.
I have a direct attached storage (DAS) box that holds my drives and connects to my mini pc over usb c (10 Gbps). Works great for my needs.
I loaded True Nas onto the internal SSD and swapped out the HDD drive that came with it for a 10tb drive.
Do I understand that you currently have a SATA SSD and a 10TB SATA HDD plugged into this machine?
If so, it seems like a SATA power splitter that divides the power to the SSD would suffice, in spite of the computer store’s admonition. The reason for splitting power from the SSD is because an SSD draws much less power than spinning rust.
Can it still go wrong? Yes, but that’s the inherent risk when pushing beyond the design criteria of what this machine was originally built for. That said, “going wrong” typically means “won’t turn on”, not “halt and catch fire”.
I was thinking of something similar. Especially since the SSD is not doing much beyond running the True Nas OS. So splitting that between a HDD does not feel like it would push things that much more
Seems to be the way, this thread on the Lenovo forum supports your idea.
There is also a guy on the german mydealz forum, who is running 2 HDDs on one power connector and it seems to work for him (account required to read): https://www.mydealz.de/deals/lenovo-thinkcentre-m720s-sff-office-pc-intel-i3-8100-8gb-ram-aufrustbar-256gb-ssd-window-11-pro-hdmi-usb-c-refurbished-office-pc-2535136
Also, TrueNAS loads entirely into RAM upon boot, meaning the SSD will only be used once when the computer is powered on. So apart from that few seconds, there won’t be any additional power draw from the SSD.
Are there any power connectors coming from the power supply that do not go to the motherboard?
Those would be your best bet to apply an adapter to as it would not be pulling additional current through the limited motherboard traces.
You don’t have to power the HDD via the motherboard, I’m 99% certain. No modern PC I’ve ever seen requires this. Your manual is ambiguous about connecting an HHD - it doesn’t explicitly say connect the power to either mobo or PSU which sows confusion. Furthering the confusion is that there are two SATA power connectors but those are not for 3.5” drives, they are for low-power bs like card readers. But big power hungry drives must be connected to the PSU directly. (Check your 10TB HDD and take a look. If it actually is connected via your mobo, you could try re-directing just the power to your PSU and see if it works (it will)).
For your new HDD, just see if there’s a 4-pin Molex from your PSU that is unused and get an adapter, or get a splitter for one of the existing SATA power cables from the PSU and stick it into the HDD, alongside the SATA data cable from the mobo.
Two more minor issues:
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Your power supply might struggle with any more than 2 HDDs. Since you’re just putting in a second, you should be good, but maybe check your PSU to see if you have any headroom. Your manual says you might have a 180W PSU, or a 210W or a 260W. It’s worth taking a look to avoid any future problems.
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Are you using TrueNAS to run these drives in RAID? If so, as far as I know, with TrueNAS RAID you can’t mix different HDD sizes in a RAID. Or you can, but it downsizes to the smallest drive size, so you’d effectively have two 8TB drives. If no RAID then I think you’re golden.
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I went to a local computer store and they were not very helpful. I asked if I could use a splitter for the power port and they said I would fry my board.
They aren’t wrong. Those SATA power splitters can be problematic due to subpar wiring and have been known to burn/melt.
Another thing they may have in mind is ATX PSUs. The pinouts on those for the same physical plug vary not only by maker and model but sometimes even by year. So if you get an aftermarket ATX-to-SATA cable that fits just fine in the SATA plug on your ATX PSU, it may put 12v on the 5v and fry your drives or mobo when you plug it in even if it’s from the same brand.
Don’t ask me why there is a voltmeter on my desk.
Those are the molex to sata power adapters that are a fire hazard. I haven’t ever heard of this type causing issues and have been using them for years and years without issue.
Yes, exactly. The shop was probably thinking of the cheap Molex ones.
There’s also the possibility they’re referring to the current draw through the mobo connector itself frying things. A couple of HDDs at 12V, 10W will be pulling almost 2A which can be a lot for some circuit board traces, but there’s no great way know what the board can handle without documentation from the manufacturer or someone with relevantt engineering experience well above what a typical computer repair shop would have.
If I were OP I would just roll the dice and try it out. Its not as if old Dell office PCs are high dollar items.
Also a good point. Speaking of, that generation Optiplex SFF had a 300W PSU as an option in the XE3 variant (basically a 7050 meant for point-of-sale use) vs the stock 180W PSU. It’s plug-and-play, too. One of my Proxmox nodes runs a 7050 SFF with that PSU. It’s rock solid.
I use a similar Dell Optiplex 7000 series.
It boots from the NVME, with an 8TB 3.5 disc for data, and a 500GB SD for my VMs. (Since spinning disks can idle much lower than SSD, getting my always-on VMs off the big drive lets it idle, with the SSD peak power being lower than the peak of spinning disk Adding the SSD increased net power slightly).
I use a splitter on the 12v power line for both of the drives. It’s fine.
This box only has an 80w power supply, and with both those drives hooked up it draws 20w at idle, and peaks at 70w when converting multiple videos simultaneously.
The manuall tells you what you can do without voiding the warranty.
Edit: Given it’s age, I’d pull the CPU cooler and replace the paste. It’s likely hardened by now. Mine was randomly rebooting because the cpu would overheat. Replaced the thermal paste and its been rock solid since.
Acronyms, initialisms, abbreviations, contractions, and other phrases which expand to something larger, that I’ve seen in this thread:
Fewer Letters More Letters PSU Power Supply Unit RAID Redundant Array of Independent Disks for mass storage SATA Serial AT Attachment interface for mass storage SSD Solid State Drive mass storage
4 acronyms in this thread; the most compressed thread commented on today has 11 acronyms.
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