It was a bit more difficult to make the Mac/PowerPC version of our benchmark as I needed MacOS 9 or X to run CodeWarrior 7.1 dev IDE. After realizing how bad idea was to try MacOS X (10.2) inside PearPC on Windows I’ve decided to brought a real Mac: my old Apple iBook G4 (mid-2005) which cost me about $100 ten years ago.
Apple is not much into backward compatibility these days so it was a nice surprise that with CoreWarrior 7.1 I was able to make a single binary that is executable under MacOS from version 8 to version 10.5.8.
MS Flight Simulator 3.0 running on Olivetti Quaderno PT-XT-20. Although only XT-compatible, 16-MHz NEC V30 is five times faster than original PC with 4.7-MHz Intel 8088. This means that the game is perfectly playable on this machine.
The internal 20MB Conner hard-drive is defective and needs to be repaired. However I am able to share a hard drive from another computer over a provided null-modem serial cable thanks to somebody in Olivetti who decided to add interlnk.exe and intersvr.exe to the C: ROM drive.
Windows 3.1 running on IBM PS/2 P70 with the gas-plasma display. There was a special color scheme included with Windows 3.x specifically targeted for use with this type of screens (to minimize the screen burning effect).
This little machine is a very interesting piece of engineering. It is an XT compatible (four times faster than original XT) and there is a standard 2,5” hard drive inside. Unfortunately it is hard to find any Quaderno in a working condition. Main problems are dead hard drives, bad capacitors and leaked batteries. I was given this one from an old guy who bought it new and had been using it for years in 90s. It was fully working when it was put in a box twenty years ago, but now we are unable to power it on and it looks completely dead.
We disassembled it to see what happened. The problem is probably in capacitors as there is some leakage around few of them. Backup battery was not leaked and fuses seem ok as well so I believe that we will manage to fix the unit.
Siemens-Nixdorf PCD-4ND is a 486-based laptop from 1993-1995. It was quite popular in Germany and you could have seen a few of them still in use even ten years ago (mostly connected to expensive industrial devices using a serial port).
I like how easy it was to upgrade the CPU in this particular laptop. It took about 20 seconds to remove a small plastic cover and replace the CPU board. There were probably four options during the lifecycle of the machine – 25-MHz 486SX, 50-MHz 486DX2 and 75-MHz/100-MHz 486DX4 (Intel called it ‘Intel DX4’).
Note the WDC graphics chip below the CPU board slot. It shared the bus with the CPU as it was connected using VLB (= VESA Local Bus) instead of the older ISA/AT bus. This allowed to use fast 32-bit transfers on a frequency equal to the CPU external clock (25/33-MHz) without a sophisticated bus controller (EISA, PCI). This chip was used in many laptops of this era and it was surprisingly powerful. It allowed up to 1024×768 with 256 colors and 640×480 with 65k colors and it could accelerate bit-block transfers as well as graphics primitives.
IBM PS/2 Model P70 (1989) on the left side and Toshiba T2200SX (1991) on the right side. The IBM machine is equipped with a gas-plasma display and Toshiba has a typical side-lit passive-matrix LCD. The photo can hardly show how superior the plasma screen is. Its black is so deep that it cannot be beaten with any modern LCD. It is as fast as CRT monitors (unlike passive-matrix LCDs with 300ms response time) and as sharp as active-matrix LCDs (that were introduced a year after this machine).
There are no plasma screens in laptops today so where was the catch? It was in power consumption which was significantly higher. Typical machine with a gas-plasma display was either AC-only or with battery life usually up to one hour. Active matrix displays started to be affordable in 1992-1993 and with their color capability and lower power consumption they pushed plasma screens out of the market. Until then gas-plasma displays were the hi-end choice for many portables.
IBM PC was not intended as a high-performance workstation back in early 80s. It could hardly be so with its slow CPU, limited graphics capability and a single-task operating system. However, IBM had an answer for performance demanding users requiring multi-tasking UNIX workstations. It was called IBM RT (known also as IBM RT PC) and was introduced in 1986.
There is some interesting history behind this computer. IBM had a RISC technology way before others (early 70s) but it required to pass a lot of internal processes and bureaucracy stuff to get it working in a custom chipset – IBM 801 CPU. IBM RAMP was introduced in 1986 and it was a spin-off project of the original CPU architecture. This 32-bit CPU was made of multiple chips on a single board and the computer needed another board to handle floating-point calculations in hardware (which was optional).
The first (6-Mhz) version of the system was quite underpowered in comparison with workstations based on MIPS R2000 RISC CPUs. This was not the only issue on the competitive market with well-established players like Apollo, DEC, HP and Sun. AIX* (IBM’s UNIX implementation) was not 4.2BSD compatible which resulted in limited software availability. IBM didn’t give much support to this product and company salesmen had no reason to push it due to low commissions.
The system used custom 32-bit bus for CPU cards and memory. Other cards like graphics adapters or storage (ST-506, ESDI) and network (token ring, Ethernet) controllers were designed for standard 16-bit AT slots fully compatible with PC line.
There were four graphics adapters available. Two with resolution of 720×512 in monochrome (black & white) or with 16 colors (out of palette of 64 colors) which were combined with 15-inch CRTs. Other two adapters offered 1024×768 (1-bit monochrome) or 1024×1024 with 256 colors out palette of 4096 colors and were combined with 19-inch CRTs (with 60hz refresh rate). Unlike standard PC graphics cards, these supported BitBlt transfers, line draw and image copy/merge to offload graphics operations from main CPU.
IBM RT was used for certain CAD applications and for shopping store control but it was not very successful on the workstation market.
When I tried a composite video output on my Bondwell Model 8 for the first time I was disappointed that there were no colors in the picture. I searched over the internet and old reviews and found that the output is “monochrome only”.
Bondwell used the V6355 chip sold under Yamaha brand. This chip was quite popular in early CGA laptops (and MSX computers) and according to a datasheet it can handle multiple output modes: digital monochrome LCD, TTL RGB, analog RGB (for SCART connection) and color/mono composite. The problem is that the chroma pin on the chip is shared with signals required for LCD and wrong voltages/clocks on the pin could damage the LCD screen.
It looks like engineers wanted to have color composite output as there are missing parts on the logic board around these signal traces. However there was probably no business justification for having it in the laptop. Mobile users used the composite output mostly on the road when stayed at hotel (any hotel TV was better than the first generation of laptop LCDs).
I have found that Toshiba used monochrome TV outputs on their LCD CGA laptops as well (and IBM probably too). Since adding a color burst logic to the laptop would need heavy hardware modifications and some disassembling of BIOS I have to stay without a mobile device that could handle special multi-color (>4) CGA modes.
