This details my TurboXT building adventure. All of my other XTs are genuine IBMs, running at 4.77MHz, with Intel or AMD 8088 CPUs. I decided to take my crustiest of the IBM machines and rebuild it with a TurboXT clone board. I also wanted certain extras, like NEC V20 CPU, OPL3 audio, CompactFlash slot, VGA graphics, and such.
First things first, take out the original IBM XT board. This one is loaded with 640KB, and has a V20 in it with a math co-processor. I’ll probably sell it on eBay at some point with just a basic 8088 CPU for someone’s authentic IBM building adventure.
I’ve got a decent selection of 8088 CPUs and V20 CPUs. Of course the new build gets a V20. I found an 8MHz Math Co-processor and threw that in as well.
The new clone board didn’t come with a BIOS. At first I was irritated, because I didn’t have BIOS chips laying around. This led me to the discovery of open source XT BIOS code. That was it, I had to go on eBay and order an EEPROM programmer and EEPROM chips, direct from China. Once I had programmer and chips in hand, I burned the XT BIOS from OpenSOC86, threw the chip in, and it fired right up! I also burned a Phoenix BIOS and it worked as well but I was aiming for open source. Plenty of chips left for more BIOS play!
This is a shot of the freshly rebuilt system with turbo clone board. Right now we have the 8MHz Turbo board with full 640KB, 10MB MFM WD10 HDD and 360k floppy drive.
The cards are, starting from slot 1: Paradise VGA, HyperCLOCK, ReSound OPL3, Parallel/Serial, Floppy controller, ST11 HDD controller, and hidden underneath an XT-IDE CF Adapter. Pics of each card below.
Amazingly, I found all short cards for this build!
First time setup to play some OPL3 tunes thru the big stereo! The Vintage HDD has IBM PCDOS 2000 and basic utilities on it, and the 2GB CF card has music files, other apps and games. This way, I can hear the authentic vintage HDD sounds as it loads.
A Super XT in disguise…original IBM chassis and you’d never know how extra awesome this thing is from the outside. I need to clean up the chassis a bit.
All the Cards
Kouwell KF-503C 360k Floppy Diskette controller
HyperCLOCK card by HyperMicro. Keeps dates beyond Y2K in conjunction with PC-DOS 2000
Paradise Systems VGA Card PVGA1A-JK
Modern re-implementation of OPL3 (Adlib Gold) using YMF-262
Seagate ST11 Hard Disk controller
Compaq Serial/Parallel combo card
Open Source XTIDE card type XT-CF