Olivetti Quaderno PT-XT-20 (1992) – part 1

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This little machine is an XT-class computer with 16MHz NEC V30HL, 1MB of RAM, double-CGA 640×400 graphics (AT&T6300/Toshiba compatible), MS-DOS in ROM and a 20MB Conner HDD (working in 8-bit mode). Its size and weight are halfway between regular laptops and handhelds (it is ultra-portable even by today’s standards). I got one three years ago and it was dead like almost all of them nowadays. The issue was “easily” fixable by replacing all the SMD capacitors. We replaced the ones on the logic board and the computer booted. However, the screen was not able to retain the contrast value, which made it hardly usable. Also the Conner drive had the head stuck (a common issue, that I want to fix later). We disassembled the lid and replaced a capacitor on the display board. Everything worked flawlessly when disassembled. As soon as we assembled the machine together, it stopped working. We were tired and put the whole thing into storage.

Recently, after three years, we gave the machine another chance. Disassembled it, booted and everything worked ok (except the HDD of course). After assembling it back? No sign of life… The issue was caused by too long legs on the new capacitor in the display board. The legs were sharp and went through the insulation layer on the (metalized) screen cover and shorted the capacitor (I know, shame on us…). Once we fixed this, we were able to put the machine back together and enjoy it. David also replaced cracked internal plastic parts using a 3D printer.

Now we have a trouble-free machine in a perfect shape with just one flaw – a faulty hard drive (and no floppy drive). However, that is not as big issue as one might think…

DEC Multia Restoration #2

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In the first part, I cleaned this little machine and convinced it to boot. Sadly, it died an hour after the first start. Anyway, you can see photos containing:

  • Video card self-check (color stripes)
  • ARC firmware for loading Windows NT (blue background)
  • SRM console integrated in the firmware for booting UNIX and VMS (black background) … yes, it has dual firmware
  • Digital Tru64 UNIX boot
  • CDE graphics environment

Today, I will try to replace two suspicious chips. Let’s hope that it will bring the machine back to life.

DEC Multia Restoration #1

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Multia (1994) was the smallest Alpha-based computer made by DEC. It was intended as a low-cost workstation but never was really successful. One of my colleagues, a former DEC employee, gave me this machine in a non-working state and – being my first and only Alpha-based system – it deserved to be fixed.

I’ve completely disassembled the whole computer and cleaned every single component inside to get rid of dust and ugly mold smell. Minor issues were found and easily fixed. There were some partially disconnected cables which probably caused that the system didn’t want to boot when was found again in storage by the original owner.

Multia was incredibly small even by the office PC standards back then. DEC managed to squeeze a 64-bit Alpha CPU, enough RAM slots, 2-MB 2D graphics accelerator, Ethernet controller, IDE interface, PCI slot and two PCMCIA slots (bottom side) on a small mainboard. The hi-end configurations (like this one) were offered with a small PCI riser containing a SCSI controller chip combined with a 3.5-inch SCSI hard drive filling the last empty space inside the case. As a result, these configurations overheated significantly.

SGI Visual Workstation 320 restoration #1

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SGI 320 is an interesting piece of history – a failed attempt of UNIX workstation manufacturers to dominate the professional PC/Windows market. Czech SGI guys gave me this computer for free a year ago when they moved to a new office building.

Unlike standard computers of the era running Windows, this one is not PC compatible. It supports only Windows NT 4.0 and 2000 and only via a special loader. You cannot run DOS on it. The logic board badly needs to replace all capacitors (some of them are already leaking) and one voltage regulator which tried to desolder itself from its position. On the other side, it still POST without any issue and passes all tests.

Now I have to wait a few weeks for all the ordered parts. This oddity deserves to survive. I’m really curious about the performance achieved by the unified memory architecture when working with analog (AV in) and digital (firewire) video signals and OpenGL.

The OpenGL performance shouldn’t be bad. John Carmack used the SGI 320 workstation when working on Quake 3 Arena…