Subj : Re: Homebrew pi400 To : Theo From : Theo Date : Wed Dec 11 2024 18:45:01 Theo wrote: > The Natural Philosopher wrote: > > On 11/12/2024 16:46, Daniel wrote: > > > Andy Burns writes: > > > > > >> Daniel wrote: > > >> > > >>> Jeff did a teardown on his second channel and soldered a m.2 socket > > >>> hoping it was properly designed. He found the power lines weren't traced > > >>> in so no power. > > >> > > >> There were some nearby component missing too, maybe the Rev1 board has > > >> bugs, and they need a Rev2 (or whatever) but his soldering job looked > > >> relatively clumsy (bridged pins etc). > > > > > > Yeah, it was pretty bad, at least he was honest about it. > > > > > > I am sure things were missing to keep the circuitry disabled and I'm no > > > engineer. > > > > Why would you put support chips on if you were not going to install an > > M.2 socket anyway? > > > > I think he called it right in that this is a bare bones model, and more > > upmarket versions will emerge in due course. > > Looking at: > https://www.jeffgeerling.com/sites/default/files/images/pi-500-m2-socket-install.jpg > https://www.jeffgeerling.com/sites/default/files/images/pi-500-pcb-bottom.jpeg > > I think there's a MOSFET and some decoupling capacitors missing (to the left > of the middle larger hole), so the power isn't connected. There may be a > pair of missing capacitors in series with the PCIe lane, but I can't > immediately see the footprints for those. Ah, I see them now. To the right of the spot on the silver chip are four tiny spots for passives, oriented at compass bearing 135 degrees. I can't tell from the photo or video whether they're populated or not, but those will be the series capacitors. Theo --- SoupGate-Win32 v1.05 * Origin: Agency HUB, Dunedin - New Zealand | Fido<>Usenet Gateway (3:770/3) .