Comparing Toshiba’s and IBM’s New Laptops

Richard O'Reilly designs microcomputer applications for The Times

Two of the most attractive laptop computers to be introduced recently are the Toshiba T1100 and the IBM PC Convertible.

They are similar yet differ in important ways in how they attempt to provide MS-DOS software compatibility in a lightweight, rechargeable, battery powered, easily carried portable computer.

The $1,999 Toshiba T1100 comes with 512 kilobytes of operating memory (RAM), a single built-in disk drive, an 83-key keyboard and an 80-column by 25-line liquid crystal display that shows black characters on a light gray-green background (the kind used in digital watches and calculators). It comes with MS-DOS 3.2 (but not Basic) and a very nice vinyl case for carrying its nine pounds.

The $1,995 IBM PC Convertible is equipped with 256K of memory (expandable to 512K), two disk drives, a keyboard with 78 keys, a similar flip-up LCD display screen and a very nice carrying handle to heft its 12.2 pounds. The handle also does double duty as a wrist support when typing. IBM’s PC-DOS 3.2 is $95 extra and includes Basic. Additional memory, in units of 128K, costs $195.


Both machines have 3 1/2-inch disk drives that use sturdy plastic-encased diskettes small enough to slip into a shirt pocket. Since desktop MS-DOS computers such as the IBM PC and its multitude of imitators use 5-inch diskettes, the problem with these portables is how to run existing MS-DOS software on them.

Toshiba, in my opinion, opted for the best approach. It offers a $599 external 5-inch disk drive that can be plugged into the portable and defined as either the primary (A) or the secondary (B) drive. A second 3 1/2-inch drive is also available as an external unit, priced at $499. Thus, the Toshiba can run standard MS-DOS programs--including copy-protected ones--on 5-inch disks.

IBM, on the other hand, has no 5-inch drive option for the PC Convertible but does offer 3 1/2-inch external drives that can be attached to its various desktop PC models. Therefore, you either have to buy new software for the PC Convertible on 3 1/2-inch disks or equip a desktop PC with the external 3 1/2-inch drive and copy software from 5-inch disks to the smaller format.

That will prevent you from using your existing copy-protected software, such as Lotus 1-2-3, on the PC Convertible unless you can overcome the copy-protection feature by using a program such as Copy II PC.


In fact, for this review I made software copies on the Toshiba to run in the IBM portable. I found both machines quite compatible with desktop PC software, although my tests were by no means exhaustive.

While both the Toshiba T1100 and IBM PC Convertible have LCD screens, there are differences between them. Proportion, for instance. A normal desktop PC has a screen that is 1.5 times as wide as it is high, and text characters and graphics images are designed to look normal with those proportions.

The Toshiba T1100 has a screen 2.3 times wider than it is tall, and the IBM PC Convertible is even more stretched out at 3.1 times as wide as it is tall. The result is that characters are more squat and graphic images are flattened.

I liked the Toshiba’s slightly more upright character set better than the IBM’s.


But I seriously disliked another feature of the Toshiba screen. It is built to display high-intensity (or bold) characters with a blinking underline under them. Many programs use such characters in their command menus, and the sight of all those blinking underlines drove me nuts.

However, if you ask for it, your dealer or Toshiba will give you a utility program that disables the blinking underline. The IBM screen simply ignores the high-intensity attribute and displays them like other characters.

I found the IBM screen more difficult to see, primarily because it remains more vertical than the Toshiba’s and so is more difficult to light properly for maximum contrast.

The Toshiba screen will actually fold back flat on the unit, making it ideal for real laptop work (the IBM would be hard to see on an airline pull-down seat table.) Another reason for the full fold-back of the Toshiba screen is that the computer comes equipped with a port on the back allowing you to plug in a standard color monitor, and the LCD screen folds neatly out of the way.


IBM requires you to buy a $325 adapter, which attaches to the back of the PC Convertible, to allow it to run a color monitor. Its LCD screen easily detaches to get it out of the way.

IBM also requires another add-on adapter ($195) to connect a parallel (or serial) printer, while the Toshiba comes with a built-in parallel printer port. An alternative to the IBM parallel/serial adapter is a $295 dot-matrix thermal or ribbon printer that attaches to the back of the PC Convertible. If you buy a special cable ($45), you can detach the printer and set it beside the computer. Either way, it runs off the computer’s internal rechargeable battery.

The Toshiba offers an internal 300-baud modem option for $249 that also adds an external serial port for connecting a faster modem or other device. IBM’s optional internal modem is a 300/1200-baud unit that sells for $450.

Given the add-on nature of the IBM design, a unit equipped with 512K of memory, a modem and the attached printer will be bulky, extending the base machine’s 14-inch depth to 18 inches and upping its price to $3,135. Weight will climb to 16 pounds.


When you’re at the office, you probably would also want to attach the monitor adapter, which is easily snapped off the back when you want to travel. That will add to the system cost but not to the bulk and weight that you have to carry.

The modem-equipped Toshiba will not increase in size (not counting the external drives) and will still weigh less than 10 pounds. But, of course, it doesn’t have a printer, so you would have to add the cost and weight of a portable printer to make a fair comparison.

Finally, let’s compare keyboards. The IBM, with five fewer keys, really stands out because of the way its keys are placed. An inverted T-shaped set of cursor keys is at the lower right, close at hand. Toshiba put its cursor keys in a row above the standard 6, 7, 8 and 9 numeral keys, where it’s a real stretch to reach them.

IBM put the 10 programmable function keys in a single row across the top of its keyboard, while Toshiba bunched them together in two horizontal rows of five across the left top of the keyboard.


Toshiba maintained the shared functionality of the cursor and numeric keypad keys as on a standard PC keyboard, but it placed those keys horizontally atop the right side of the keyboard. IBM embedded the numeric keypad in the normal alpha keys, accessing them with a special function and number lock key sequence. The result is that running spreadsheets and doing word processing is easier on the IBM than on the Toshiba keyboard.

So, as I’ve found on all of the laptop portables that I’ve tested, the IBM and Toshiba are compromise machines: IBM gives you two drives instead of one, a nicer keyboard, a faster modem and an attached printer, while Toshiba makes it easier (or possible) to use existing 5-inch diskette software, has a better LCD screen, is cheaper, lighter and smaller and doesn’t require accessories to run external monitors or printers.

(Just as Computer File was going to press, a Toshiba representative revealed that the company will announce an upgraded replacement at the National Computer Conference on June 16 to be called the T1100 Plus. According to Toshiba, the new machine will have a faster 80C86 microprocessor running at 7.16 megaherz, two internal 3 1/2-inch drives, 640K of RAM, a built-in serial port in addition to the parallel port, better color resolution on external displays and the optional internal modem will be 300/1200 baud. The price is not yet available.)