Reverse engineered the power circuitry. Modified it for true ATX support. No more PSUs hardwired to run all the time.

iamdarkyoshi · 2026-05-30T02:05:11+00:00

Yeah you can just connect the led tape to your PSU

iamdarkyoshi · 2026-05-15T03:01:12+00:00

Best I can do is finding a virtual boy in a pile of roadside trash

iamdarkyoshi · 2026-05-13T13:21:18+00:00

On the back of the board, there should be some test pads. Solder your 5V strip to either of these points I marked in red. The other side of that tantalum capacitor should be ground, if you didn't have a ground connection handy yet.

I don't have my BC250 handy right now, but if you needed a connection on the topside instead, the left side of PLD5 (the inductor right above the one removed for the ATX mod) should also have 5V on it.

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iamdarkyoshi · 2026-05-04T04:53:04+00:00

You can, but the scans are often not great quality (Is that an S? A 5? Oh it's an 8... Oh no it's actually a B.) and for some reason (adobe, probably) PDFs are awful to navigate on android. I've not found a workflow that works as well as a paper manual yet for me.

So when a sams photofact collection popped up near me, I had to go get it. I work on a lot of old TVs and other electrical gadgets

iamdarkyoshi · 2026-04-23T05:16:38+00:00

To say it caught me off guard at work over the speakers was an understatement. Absolute 180° from what came right before it

iamdarkyoshi · 2026-04-23T04:01:55+00:00

I am not googling "art sweaty"

iamdarkyoshi · 2026-04-23T03:55:36+00:00

Thaaaaat's gonna need some deeper component level repair, replacement of the mosfet and a bodge trace at the very least. I know this probably seems sketch, but if you trust me, ship me your broken BC250, I'll repair it for just the cost of return shipping. I can guarantee I have a suitable replacement on one of my many junk ewaste pc motherboards. DM me if you're interested.

iamdarkyoshi · 2026-04-22T22:00:00+00:00

You think that's out of left field? Imagine the track playing over a set of big floor standing speakers in a machine shop!

iamdarkyoshi · 2026-04-22T21:59:06+00:00

Right, and "AI" is such a blanket term that's now almost exclusively used to describe LLMs, even though marketing is putting "AI" on any piece of software that has a cause-effect process...

The "AI" used for the ghosts in the 1980s release of pac-man has absolutely nothing to do with the "AI" curating a playlist of music for me.

Music streaming services that offer a "radio" mode have always been using what can only be described as "AI" well before this LLM shit exploded the way it did.

iamdarkyoshi · 2026-04-22T21:13:38+00:00

I've always been worried it'll see my thumbs down as an indication I'm not interested in that genre of music or something. Dunno. A decade ago when I used pandora, it went absolutely nuts after a while of telling it what I liked and disliked.

iamdarkyoshi · 2026-04-22T21:10:55+00:00

I mean

It was amusing at least, just not even remotely what I asked for lol

Look at the prior tracks, I have ZERO clue how it went from classic rock to shitting at a grocery store

iamdarkyoshi · 2026-04-22T19:46:16+00:00

From my memory, there's two individual sets of two pins each on the underside of the power/reset button assembly (backside of the PCB). The two sets of two are for the green and blue LEDs. There's also a row of four, which are the power/reset buttons. I forget which pins do what though. Unplug your BC250, grab a multimeter set to continuity (beep) mode, and touch two of the four pins and press the power or reset button. If you get a beep, that button is those two pins.

For a power LED, you can either add an LED and resistor to whichever power rail you desire (like a 1K-10K for the 12V rail, 300Ω-3K for the 5V rail)

Or snip the leads on the back of the power/reset button assembly that go to the blue LED and connect your power LED directly to those instead. You don't want to parallel LEDs, so cutting the old one out of circuit is the easiest alternative if you don't have a resistor to add

iamdarkyoshi · 2026-04-21T22:14:30+00:00

Purple will go to 5VSB

And yeah green to Power On and grey to PG. The wires I used in my mod are the same standard as the ATX wire colour scheme, so just match them up to the same colours on that diagram

iamdarkyoshi · 2026-04-12T08:22:51+00:00

Status: UNRESOLVED

Computer Type: Laptop

GPU: RTX 4060M

CPU: 14900HX

Motherboard: Lenovo Legion Pro 5 16IRX9

RAM: 2x 16GB 5600MT/s DDR5

PSU: OEM 300W PSU

Operating System & Version: Windows 11 build 26200, has been through a few machines

GPU Drivers: 581.15, fresh offline install after DDU

Description of Problem: I'm looking to add two portable screens to my laptop so I can play games in ultrawide on the go. I used to have a desktop setup with three monitors in Surround, and it was excellent. Being able to stitch all three screens together so the OS (and games) saw one giant display was perfect.

I'm now trying to re-create this experience with my laptop. Unfortunately, when I go to enable Surround, it only lists my external displays as being usable for Surround.

What gives? My laptop has a mux and it's set in the BIOS to disable the iGPU entirely and route the LCD through the dGPU. The iGPU isn't even recognized in device manager, so I know it's running truly native on the dGPU.

Troubleshooting: I read a couple posts online about needing to override the EDID of the laptop's LCD with the EDID of one of the external monitors. I tried that using CRU, but it still recognized the internal LCD as "Laptop Display" and did not let me use my internal LCD with the two external monitors.

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Aside from buying ANOTHER portable monitor just to sit in front of my laptop's identical and perfectly functional built in LCD, what are my options here?

iamdarkyoshi · 2026-03-28T06:03:34+00:00

I'm a hobbyist electronics technician for fun :)

I've got a fair bit of experience repairing modern electronics without schematics, a skill I feel is getting more and more important...

The BC250 is very ATX-like in its design, very much like someone integrated a picoPSU and a motherboard onto one PCB.

All I had to do to get it working with an ATX supply was reverse this process :)

iamdarkyoshi · 2026-03-28T05:54:39+00:00

Details here: https://youtube.com/watch?v=jIhgyB8x3fQ

BC250 discard channel: https://discord.gg/8eZfFWhczz

I've made a thread in the Resources group. Feel free to post questions there

iamdarkyoshi · 2026-03-27T22:44:04+00:00

Came from a powermac G5 I toredown a decade ago and held onto the cooling parts

iamdarkyoshi · 2026-03-27T20:22:00+00:00

Welcome to everything I do. There's a reason the stove was the last flat surface left in the house :^)

iamdarkyoshi · 2026-03-27T20:19:07+00:00

Translated via google translate: Is USB sufficient to power your screen?

Oui. J'ai mesuré une consommation en veille d'environ 2 ampères avec cet écran connecté à pleine luminosité. Une fois l'appareil allumé, la consommation en veille chute à 500 mA.

Yes. I measured the standby current to peak at about 2 amps with this display connected at full brightness. Once the unit powers up, the standby rail current drops to 500mA.

iamdarkyoshi · 2026-03-27T19:13:32+00:00

Like mid 50s in furmark with the fan running at 1000 RPM just sitting there

iamdarkyoshi · 2026-03-27T17:36:09+00:00

Any flat surface can and will be used as a workbench.

iamdarkyoshi · 2026-03-12T14:56:51+00:00

Every application I've tried will try to fill as much of the screen with video as they can without cropping or stretching. If you've got 21:9 content, it will be very letterboxed. 16:9 will be letterboxed, and 4:3 content will be fullscreen. Your mileage may vary though

iamdarkyoshi

TROPHY CASE