NEC V20 vs 8088-2
doing stuff and timing it
I decided to benchmark my 8088s previously, but benchmarks aren’t exactly the most useful way to get a sense of how these chips truly perform in day to day use. Accordingly, I am going to test the ceramic 8088-2 against the NEC V20 in two real-world usage scenarios. First, we will test page loads in the MicroWeb browser. Second, we will test turn times in Civilization. I should note that my XT-class machine is fitted with an Intel 8087 coprocessor, so if you are going to try to replicate my results, be sure to account for that.
The Real World Tests
On the NEC V-20, a single load of 68k.news via the MicroWeb web browser took roughly 56 seconds.
On the 8088-2, the same task took roughly 76 seconds.
On the V20, one turn calculation in Civilization was roughly 1 second. This would lengthen considerably as the game progressed.
The turn time on the 8088-2 was roughly 2 seconds.
It took roughly 16 seconds to go from the Civilization settings menu to the Civilization intro screen on the V20.
The load time from the settings menu to the intro was equivalent on the 8088-2.
On the V20, it took roughly 27 seconds to load the save file and populate the screen.
On the 8088-2 the load time for the save file was about 29 seconds.
With these results, it is clear that the V20 is truly the faster chip. The difference at 9.55 MHz between the ceramic Fujitsu 8088-2 and the plastic NEC V20 isn’t so great as to be life changing, but it is noticeable.
What is the NEC V20?
NEC began producing 8088 and 8086 CPUs as a second source for Intel in 1979. This wasn’t at all uncommon in the early days of ICs. Hardware manufacturers wanted to be assured that should a supplier suffer production issues there would be another source for the IC in question. NEC, however, wasn’t satisfied with just being a second source. As a result, they made the NEC V20 and released it in 1984. This unlicensed chip did result in some litigation by Intel against NEC. As a result, NEC paid royalties to Intel. Later versions of the V20 improved both performance and power consumption, and these later chips hit clocks up to 16 MHz.
2 micron CMOS process
4.77 Mhz, 7.16 MHz, 9.55 MHz modes
Two internal 16 bit data busses allowing two concurrent data transfers
8 bit external data bus
20 bit address bus allowing the addressing of 1MB of RAM
8080 emulation mode
Includes 80188 instructions
Pin compatible, drop-in replacement for the 8088
In almost all cases, the NEC V20 provides an increase in performance over the 8088 when running at the same clock speed.
Networking and DOS
Now, getting online with DOS isn’t straightforward. As DOS predates modern network standards, you’ll need to do some research. I use an NE2000 compatible NIC and driver developed by Sergei Kiselev. Armed with this, I then use mTCP to get things going.
In my AUTOEXEC.BAT
Then, within TCP.CFG
Then we need to load the driver, and run DHCP to get an address.
LH NE2000 0x60 2 0x300
With this out of the way, we can run MicroWeb, or we can use the mTCP tools. Obviously, your packet driver and settings will likely be different from my own.