You read the title correctly – the Toshiba T4400SX has an amber gas-plasma screen, but it’s not a luggable like the IBM PS/2 P70, and it’s not a large laptop like the Toshiba T5200… it’s in a notebook form factor! Additionally, it can run on battery power, making this one of the few battery-powered machines available with such a display.
Two versions of the T4400SX exist: one with a traditional monochrome LCD, and the far more rare plasma model. There is also a color variation, the T4400SXC. Typically, the only way to distinguish these models from each other is by looking at the bottom: the plasma model says “T4400SXP”. It took me 8 years to find one of these for sale – I had it on several watch lists from 2013 to 2021!
Here are some pictures of the plasma model. Unfortunately, even with a bench power supply at the requested 21V, I am unable to get the machine to boot, as when I turn it on, the battery LED blinks 1-1-1-0. There is more information about how to power this machine available at this page.
Like most Toshiba laptops of the era, this has a rechargeable RTC (Real Time Clock) battery, as well as a standby battery to keep the system running (in standby mode) while you are changing main battery packs. Unfortunately, these are known to leak eventually, so get them out while you can!
Finally, like many IBM portables of the era, the Toshiba T4400SX uses IC DRAM for memory expansion:
Hi Jack,
Like other Toshiba laptops from this time, your T4400SXP likely needs all the capacitors in the DC/DC module and motherboard replaced. I suspect that if you do this, it will have a pretty decent chance of firing up!
I agree that it most likely needs that! I did that years ago with my Toshiba T1960CT, which was refusing to power on with a similar blink code, and it’s been working great ever since. In this particular case, though, I was a bit discouraged when I read about the handshaking the power supply does with the laptop. It’s a very odd power supply that I don’t have, and I’d hate to do a recap and still have it not work. Either way, if I end up recapping this, I’ll document it and make a capacitor list like I did on my CL57SX page last year.