Yes, these really existed. I actually was naive enough to purchase one in early 1998, when I was looking to replace my IBM Aptiva's 4X CD-ROM drive. I found this at my local Office Depot, and I it was priced between $150-$200, if I recall correctly. I originally had my sights set on Creative Labs' new 32X CD-ROM drive, which I clearly should have purchased instead.
The box contained a CD-ROM drive with a "Smart 100X" label printed on the drive door (this was really a 24X drive), a Win95 driver disk, manual, and a Yamaha wavetable sound card. The sound card was probably included as consolation for being ripped off.
In short, this could theoretically achieve "100X" speeds, but there was a huge catch. This used a specific 32-bit CD-ROM driver that would copy a portion of the CD-ROM's contents to the hard drive. The CD-ROM "seeks" would come from the hard drive, and not the CD-ROM.
In early 1998, the newest consumer-grade PCs were shipping with the Intel Pentium II at 333 MHz . PCs with 100 MHz front side bus Pentium II processors (350/400/450 MHz) didn't ship until later in 1998. The IDE hard drive interface on PCs from early 1998 were improved, allowing for a theoretical maximum data transfer rate increase from 16.6 Mbps to 33.3 Mbps. If we do some basic math, a 1X CD-ROM is capable of about 150 kilobytes/second, so 100 times that is about 15 Mbps. The newer 33 Mbps interface was supposed to guarantee that we'd see those speeds...but I doubt such speeds were actually achieved. Also, a 650-700 MB CD-ROM image would consume a huge amount of the typical 3.1 to 4.3 GB hard drive of the time. If you had an 8 GB drive, which would have been monstrously expensive in early 1998, this may have worked; however, it took forever to transfer the CD-ROM data to the hard disk. I thought the included driver/software allowed the user to limit the hard disk buffer size, but I can't remember.
My problem was that my system (an IBM Aptiva 2168-M series tower) had a Quantum Fireball 1080AT disk (1.0 GB) with an IDE interface from 1995, which wasn't capable of 33.3 Mbps. As you might have guessed, copying CD-ROM contents to a disk with less than 400 MB of free space was not going to happen. But I was 17 at the time, and unfortunately, this was one of life's many lessons to be learned: read the box before getting too excited.
Some new old stock (NOS) exists here. I'm not sure if this is legit, but it has some really good high-res photos: https://www.shopzonjumper.store/product/Nos-D … uzyxrurruv.html.
This would make an interesting LGR oddware video 😀
I still have the Yamaha sound card, and it's actually quite good for MS-DOS retro gaming. It's got an OPL3-SA3 FM synthesis chip, and has a decent software wavetable. FM synthesized music sounds beautiful, as one would expect from a Yamaha product. This does have the wave blaster header, so adding a DreamBlaster X2 or similar MIDI device would probably work very well, though I have not tested this.
My "Smart 100X" 24X CD-ROM drive broke about 20 years ago, but somehow I managed to keep the floppy disk containing the driver. I kept my Aptiva's original 4X CD-ROM, and it still works after 27 years.