OpenWRT x86 on a Dell Inspiron 15 N5030

Hello, everyone!

I've recently tried OpenWRT x86 on an old laptop I got around (a Dell Inspiron 15 N5030). After having used Manjaro Linux (as opposed to Arch Linux) to identify the drivers needed by my hardware (in particular the WiFi card and the 2 USB Gigabit Ethernet adapters I was going to have to use), I've identified the required list of packages and installed it on a USB stick.

My goal is this: replace the Asus RT-N56U B1 that I currently rely on and maybe upgrade while at it.
Now, that Asus has no issue, this is more about tinkering and making use of old hardware.
I'd like to see 200mbps down speeds on the 5GHz network and at least 100mbps on the 2.4GHz one.
I intend to expand on the IoT side, but for that I'd use a dedicated AP that would likely not be Internet facing - I mention this just because I know there might be client-count related issues either with the WiFi cards or maybe the OpenWRT drivers for such cards.
Right now, the apartment is flat, but it's likely the next housing will be a 2-3 floors spanning scenario, so the multiple antennas focus below isn't out of "more antennas means better!" mindset, but just to improve coverage as much as possible and also add MIMO or better support.

My current broadband connection is a DSL ~200-250mbps down / 26mbps up. The provider only offers faster connections for cable/fiberglass subscriptions, so it's unlikely I'll upgrade any time soon. The prices for faster packages in Germany are rather ridiculous too... (compared to Romania, for example - it's similar to comparing internet prices in Europe with those in the US...)

Specs:

  • Intel Pentium T4500 (2.3GHz dual core / dual thread)
  • 3GB RAM
  • some SSD
  • 100mbps on its Ethernet port
  • USB 2.0 on its USB ports (so, ~400mbps tops)
  • PCI Express 1.0 (so, 2.5gbps)

I've opened a thread on Reddit here. Without much luck.

I'd rely on the UGreen Gigabit Ethernet adapter for the WAN connection. This should be enough, even if I upgrade to a ~500mbps connection.

The PCIe 1.0 shouldn't be that much of a bottleneck - assuming everything shares that 2.5gbps space, with a <500mbps WAN connection there should be plenty of space for everything.

I changed the mini PCIe WiFi card the laptop had to a Qualcom Atheros AR9565 piece. Unfortunately, I only see up to 51mbps download speeds when running tests via speedtest.net with client devices (another laptop, a WiFi6 capable smartphone). I used it for a whole evening - streaming some news website plus a smartphone. For a 1 laptop antenna setup, it was OK. I don't think it'd work great for gaming, but for that I'd rely on a cable connection anyway.

I plan to get a 3x3 card (maybe an AR9380, maybe up to an AsiaRF AW7915-NP1) and have it spawn 2 networks, on 2.4GHz and 5GHz - just to split load between them, some devices here, some there).

I intend to design a 3D printed 'HDD caddy' mount for the extra antennas (and their cables). I was thinking maybe of using the slimline SATA port with a daisy chained adapter and maybe that could work for a more power-hungry WiFi card, or for a USB adapter of some sort that would allow using an NGFF/mini PCIe card. Putting together a custom body/case for the laptop is also fine by me.

All in all, I'd just like to make use of as many of the ports as possible for a resulting router/AP as capable as possible.

I'm aware the slimline SATA port is likely storage-only. I'm aware there might be some whitelisting for the mini PCIe port involved (I couldn't find any and I'd rather buy/test/send back some device). I'm aware it's an old piece of hardware - I have others, more recent laptops I could use instead.
I'm aware the overall costs may be amounting to almost a modern wireless router - but what's the fun in that?
Also, I'm aware I might be dead wrong on understanding some of the concepts involved, so please educate me if so needed. I'm a technical person (programmer), but the engineering and networking dimensions of life are often beyond me. Always keen to discover and understand more, however!

Any thoughts would be greatly appreciated!

skip the built in wifi, repurpose the ASUS RT-N56U as dumb AP.

The reason to use old laptop as router is "you don't need to pay extra", in case you have to buy multiple USB NIC + WiFi card (which you don't know if it works well), I probably should suggest you just to get a Cudy RE3000 and flash OpenWrt. Of course if you want to do SQM using old laptop would be better, then the RE3000 can still be a good wireless AP

As said, "I'm aware the overall costs may be amounting to almost a modern wireless router - but what's the fun in that?"

Thing is, I already had basically everything - except maybe a suitable card for AP and cables/antennas/adapters for those.

I've ordered (from Aliexpress) some stuff (Atheros AR9380-based half-size mini PCIe card, 4 RP-SMA antennas, a set of 5 RP-SMA IPX UFL cables) for practically half the cost I was looking at on Amazon (which makes me wonder why that would be so... but hey! - I kept the Amazon products in a separate list, although over there only the Netely full-size AR9380-based card costs more than all those things ordered from Aliexpress).

I'll play with it and see how it works. I'll report in about 2 weeks, when the parts get delivered.

Update: parts got here. I ran a couple of tests with some other USB-dongle with external antenna and, on 802.11n/2.4GHz, the improvement was noticeable when compared to the antenna the dongle came with (was reaching about 30mbps with the 'original', the ones from Aliexpress went to 40-50mbps).

I started making a 3D model for an adapted HDD caddy. My intention is to 'dock' the antennas in that adapter (I need to do some reading; maybe the spacing isn't great in the limits of the caddy bay itself, so I might have to adjust the adapter or make it 2-part, so that another 'module' connects to it and protrudes from the laptop case, allowing the connectors to get a tiny bit more spread out; it's just a hunch right now...).

For the sake of running a smoke test and confirm the WiFi card isn't dead (turns out the card is a Bigfoot Networks Killer wireless N 1103 now by Qualcomm), I connected 3 cables to the card and then installed the antennas. I used my couch as a makeshift cradle (imagine a _ | _ being the intersection of some of the slates in the couch; I used those 'trenches' to hold the antennas), maybe 30cm under the plane of the Asus wireless router I'm currently using.

The laptop (while running on Win10) showed a highly unstable speedtest.net session with download speeds of up to 100mbps. I don't recall what network I used (the 2.4GHz or the 5.0GHz one), so I can't say anything yet - at least it doesn't seem to be DoA.

Before I order the 3D model caddy, I'll glue together some wood-based caddy and see if the actual placement makes a difference.

Another idea is to still use the laptop antenna and only add 2 more (I'm still aiming for 3 external antennas). Maybe as the aux antenna, as I wouldn't put that instead of the main one and clearly not instead of the MIMO one.

Before-the-last report

Specs:

Bought from https://www.aliexpress.com/item/1743817536.html
Details: Atheros AR9380 AR5BHB112 Half Size Minipci-express Mini Card 450Mbps SPS:630435-001 - actually a Qualcomm / Bigfoot Networks Wireless N Killer 1103 based on AR9380

The card seems to be fine in the mini PCIe slot. After a few hours (on a rather hot day around here), it stays at 50 degress Celsius, with an environment temp of 27 degrees; the USB adapter (UGreen) goes to 34 degrees. Currently configured with 1x 5GHz 802.11N network.

The setup is stable, but far from close to being done:

Instead of those clamps plus rigged paper sheet for almost-same-plane setup, the 3 atennas will be housed in a HDD-caddy-like mount and I'm trying to figure out what tolerances I got as-is, to see how big of a heatsink I can mount on top of the WiFi card.

I am tempted to get a USB-to-MiniPCIe adapter, to see if OpenWRT will detect and use a Centrino 6205 WiFi card that I got laying around. I was under the impression that this 3x3 AR9380 card would register 2 radios, but the card is only dual-band/DB, not dual-band, dual-concurrent/DBDC (I guess that would need a 4x4 card instead; likely my confusion comes from dual-band router which can run 2.4GHz and 5GHz at the same time, while dual-band card means a card capable of operating in either frequency range, but not at the same time).
Either that, or see if I can repurpose any of the SATA ports (SATA/slimline SATA) to anything else (think daisychaining *SATA->USB->adapter->something else).

I've had the laptop running for the past 8 hours, it averaged under 15W/h in consumption, some 0.092 kWh in total. I'll leave it going for 24h and then work out the numbers, but right now it looks well within the space the Asus router I'm currently using (that one has a 12V 1.5A power source).

As far as performance goes:

  • I've tested with both another HP workstation laptop (fit with an Intel Ultimate-N 6300 and 3 incorporated antennas) and my phone (a Xiaomi device from the Redmi 11 line)
  • cyan entries: tests against the 802.11n 2.4GHz network of my Asus
  • white entries: tests against the 802.11n 5.0GHz network of my Asus
  • yellow entries: tests against the 802.11n 2.4GHz network of my Dell
  • lime entries: tests against the 802.11n 5.0GHz network of my Dell

As far as safety / compliance goes:

  • the default channel chosen by OpenWRT (when left on Auto, on 5GHz) looks like not legal in Germany, so do some research and stay safe (I did set the country code in the setup, so I was expecting this to have an impact somehow)
  • if that's not a reasonable concern, it's very likely that client devices will NOT see the network, precisely because the default channel is too big a number and it'll just not display it, even if it is technically capable (it feels as if the network has the SSID hidden, despite this not being the case)
  • wall penetration is rather disappointing, my Asus router is clearly better at this than the Dell laptop with external antennas...

Nice to haves afterwards:

  • swap the CPU cooler for a 5V 200mm fan that would then actively cool both the CPU and the WiFi card, maybe the Ethernet USB adapter as well)
  • some cronjob reporting/checking the battery level, so it'd activate at say 64%/deactivate at say 76% a Delock smart power socket (to prevent the battery from always being charged; the Li-ion cells favor often & meager charging cicles, far from 100% charging)
  • maybe have Luci display the battery level & temperature(s) in the UI, or maybe feed that info into some other consumer (those S2 i9100-s I got around here look like they'd be a nice way to display such details)

If this isn't reliable enough to become my main wireless router, it'd definitely be cool enough to serve just my office - given how the layout of my home will soon change from 1 level to 4 levels in total.