In May the Chinese company DZT created tech media buzz by offering a $199 4.77Mhz 8088 notebook running MS-DOS on the AliExpress website. I’m a sucker for old computers and couldn’t resist this newly-designed machine with the same chip and speed as the original IBM PC.
It’s still available: Book 8088 DOS system notebook CGA graphics card computer IBM PC XT compatible machine 8088 8086CPU microcomputer principle| | — AliExpress
The machine boots off a 512MB CF card, which makes disk I/O fast and convenient for installing arbitrary apps.
Construction quality is OK. It’s a step or two below what’s expected of modern electronics, but it’s not shoddy.
Like some machines of that era, it has a “turbo” mode, which boosts its clock rate from 4.77Mhz to 8Mhz.
But here’s the thing: it’s much faster than an actual 4.77Mhz 8088. I bought this machine to have a convenient, modern take on a classic computer. But at 4.77Mhz it runs 1.15 to 2.29 faster than an actual 8088.
In 1986 Chips and Technologies release MIPS.COM v1.20. It’s a benchmark that reports how fast a machine is relative to the original PC. A score of 1.0 indicates identical performance. The table below shows the BOOK 8088 varies in performance based on instruction types. The right column has results for an actual 4.77Mhz 8088 machine I have — the Memorex Commuter Computer. It has consistent performance for each instruction type.
One of the reasons I wanted this computer was to validate the performance of an 8086 emulator I wrote. I can use the Memorex for that but it’s inconvenient since files have to be copied first to a Windows 98 machine, which is the only device I have that can use the PCMCIA SRAM storage device in the Memorex. The BOOK 8088 makes copying files from my main PC a snap, but its inconsistent performance makes it less useful for validating my emulator.
If you’re looking for that ancient machine fix, I recommend the BOOK 8088. If you’re looking for an exact CPU replica, look elsewhere.
Addendum from August 5, 2023:
As someone commented, the machine had an NEC V20, not an actual 8088. I swapped out the V20 for an actual 8088. The genuine 8088 runs fine at 4.77Mhz, but is in fact still too fast — about 5% or so. I wonder if the clock is really running at 4.77 Mhz. An updated table for mips.com:
I see the same performance gain for other benchmark apps as well.
