Console manufacturers often have lots of plans for their hardware down the road, sometimes years into the platform's lifecycle. Which is why, when you first bought a console, you may have noticed proprietary ports that have no obvious or explained purpose.

If an accessory that uses that port eventually releases, then the mystery is solved, but there have been more than a few consoles over the years that sport physical ports that ended up used for nothing -- though you still had to pay for them!

5 The Nintendo 64 Expansion Port

Flip over a Nintendo 64, and you'll find a big plastic cover hiding what looks like an important slot. It was meant for a magnetic disk drive add-on called the 64DD, which only released in Japan and promptly flopped.

So, although there was actually a device released for it in Japan, everywhere else in the world, N64 owners were left wondering what this bottom expansion port was for.

Funnily enough, this wasn't even Nintendo's first attempt at a disk drive in addition to carts. The Famicom Disk System for Nintendo's hit 8-bit system was actually a decent success in Japan. Magnetic disks are way cheaper than carts, and they have more storage space. You could even go to a store and have new games written on your disks when you are done with them. However, a disk solution for the NES (Nintendo Entertainment System) in the USA never happened.

4 Sega Genesis / Mega Drive EXT Port

A lot of the time, these unused ports are only present on the first models of a console, which is why you might look at your retro console and think, "where is this port they're talking about?"

So it is with the so-called EXT port on the Sega Genesis. Not only was this only found on the Genesis I, it seems it wasn't even on all Genesis I systems. It's a 9-pin port that seems to be some sort of serial port and, according to some fans on Reddit, it's basically a controller port with a female socket instead of male. Again, there were some Japan-exclusive accessories for it like the Mega Modem.

In the rest of the world, it's an unused port that a small percentage of early Genesis consoles have. Sadly, I could not find a photo of the EXT port with a license that allows me to post it here, but there's an EXT port AV mod guide that clearly shows you what it looks like.

3 PlayStation 2's Expansion Bay

I waffled a little on whether to include this on the list, because the expansion bay on the origina; "phat" model PlayStation 2 consoles isn't technically unused, and did have accessories you could buy outside of Japan.

The thing is, this bay had a very limited level of functionality. You could install an official hard drive and network adapter upgrade, which was a requirement for Final Fantasy XI, the only North American PS2 release that must have the hard drive upgrade to work. Since it's an MMORPG and relies on online updates and patches.

However, beyond that there were a tiny smattering of games that could take advantage of the hard drive, such as sports games that could save replays, or games like Xenosaga Episode 1, which can apparently install some files to the drive to improve load times compared to playing purely off the disc. At least, that's what the Wikipedia article says, but I can't find another source that confirms it.

Either way, this expansion port had so much potential, but ended up being used for little if anything. The later PS2 Slim models dropped the bay completely, but included an Ethernet connection for online play in the package. So clearly no one bothered with the HDD.

Ironically, today's modders can use that bay to install game disc images and play them using custom firmware, making phat PS2 consoles quite sought-after in the retro market.

2 The GameCube Serial Ports (That Mostly Went Nowhere)

The GameCube has not one, but two serial ports on its underside, plus a "Hi Speed" port. Nintendo had ambitions for broadband adapters, modems, and even development hardware, but outside the Game Boy Player and a few niche peripherals, these ports were basically decorative.

By the time later GameCube revisions shipped, some of the ports were literally removed.

1 PlayStation Vita's Mysterious Top Port

I actually noticed this one right away on my launch OLED Vita (which I still use to this day) and right from the start there was basically no information. Sony never explained what it was for, but we speculated that it was for everything from video-out to debug hardware. Sony eventually admitted it was reserved for "future accessories," but no such accessories ever came. Later Vita models dropped it completely, cementing it as one of the most pointless ports in handheld history.

Vita modders haven't figured it out either, it seems, and I really would like to know, given that time and effort went into it, and the PSP before had a bunch of interesting peripherals. The thing is, the Vita already had pretty much everything built into it you could think of, so it really would be interesting to know what more could have been stuffed into Sony's last true handheld.

Sony PlayStation 5 Pro (PS5 Pro) 7 / 10 4K Capabilities HDR, Up to 8K Game support PS5, PS4 Processing Power 16.7 TFLOPS, AMD Radeon RDNA-based graphics engine Storage Custom 2TB SSD

CPU 8 Core / 16 thread AMD Zen 2 Connectivity Wi-Fi 7, Bluetooth $700 at Amazon $700 at Best Buy $700 at Sony Expand Collapse