Keeping Up with the Commodore: A Hands-On Review of the Commodore 64 Ultimate

What do 1985 and 2025 have in common? The fact that you could be reading a review of a new Commodore 64 home computer. Back then it would have been an early look at Commodore's upcoming 64C; today it's the freshly-launched and completely revamped Commodore 64 Ultimate, a backwards-compatible home computer powered by gate-level recreations of MOS Technology's finest chips running on an AMD Xilinx FPGA.

Does a YouTuber's passion project turned fully-fledged international company really mean that Commodore is back, though? There's only one way to find out, and that's to go hands-on with the first new Commodore home computer in more than 30 years to see if it delivers on the company's promises.

Hardware

• CPU: MOS 6510 at up to 64MHz, on an AMD Xilinx Artix-7 FPGA
• Memory: 128MB DDR2 available as 64kB RAM, 16MB RAM Expansion Unit (REU), 16MB GeoRAM (not yet implemented), RAM disk
• Storage: 16MB flash, 64GB USB flash drive (included), microSD Card (not included)
• Audio: Up to 8× SID 6581/8580 on FPGA, two sockets for original SID chips (not included)
• Network: 10/100 Ethernet, 2.4GHz Wi-Fi, modem emulation
• Keyboard: 66-key mechanical with Gateron Pro 3.0 White linear switches
• Joystick: 2× DE9 connectors, optional emulation via keyboard (no joystick included)
• Video/Audio: HDMI up to 1080p with optional scanline simulation, analog output with RGB, S-Video, and CVBS modes (cable not included), 3.5mm audio jack
• Expansion: IEC serial port, Memory Expansion cartridge port (99% compatible with original hardware), Cassette Port, User Port (requires breakout board, not included)
• Extras: HDMI cable, 12V PSU, spiral-bound manual, sticker sheet, >100 bundled games, utilities, demos, and music collections
• Price: from $299.99 (as-reviewed), rising to $349.99 in 2026

The Commodore 64 Ultimate looks, you'll be surprised to read, a lot like a Commodore 64 — specifically the original "breadbin" model, rather than the later Amiga-like 64C. Like the breadbin, it's surprisingly bulky for the hardware contained inside and, like the breadbin, it's finished in a warm brown-tinged gray with darker keys.

While it's being positioned as the first new Commodore home computer in 30 years, it's not strictly speaking "new": inside the recreated housing is a tweaked version of the Ultimate 64, designed by Gideon Zweijtzer as a replacement motherboard for failed Commodore 64s. The redesign does away with long end-of-life MOS Technology chips by replacing them with gate-level recreations on an AMD Xilinx FPGA. The result is something which offers something closer to real-steel hardware while bringing with it ready part availability and some very nice modern quality-of-life improvements.

The Ultimate 64, though, lacks the Commodore name, which is attached to this new, all-in-one, ready-to-use cased version thanks to the efforts of Christian "Perifractic" Simpson, a YouTuber who has spent considerable time and money acquiring the rights to the Commodore trademarks in an effort to bring back the best-selling home computer of the 1980s in modernized form.

Those who remember the original will be surprised to see the C64U coming with 128MB of RAM, given that the "64" in it name referred to just 64kB in the original model. The C64U still includes 64kB of RAM, but the extra memory isn't going to waste: you can configure up to 16MB to act as a RAM Expansion Unit (REU), a now-rare add-on cartridge released by the original Commodore to keep the platform ticking over in the face of growing software complexity; another 16MB will be available to the bundled GEOS graphical user interface in a planned firmware update not yet available at the time of this review, while the remainder is exposed as a RAM disk for temporary storage.

Almost all the ports of an original Commodore 64 are present on the Ultimate: there are two nine-pin joystick ports to the side, an analog video output, IEC serial port, the "Memory Expansion" cartridge port at the rear, even a connector for an original Datasette tape drive. The only thing missing, aside from an RF video output for analog TV tuners: the "User Port," pins for which are present inside the case on the motherboard but for which you'll need to pick up an optional breakout board, priced at $9.99.

Special mention has to be given to the power switch, which may sound like an odd thing to focus on until you take a closer look. It mimics the original in shape and feel, but hides extra capabilities: as well as controlling the power status, up for on and a long-press down for off, a flick upwards freezes the currently-running software and displays a menu for accessing disk images, networking, printer emulation, and more. It's a clever way of integrating the functionality into the C64U without spoiling the exterior appearance, and just one of the signs that a lot of attention has been paid on getting the aesthetics of the system just right.

The old stuff

The Commodore 64 Ultimate might be new, but it's building on top of a long and storied history. While its launch is likely to revitalize the homebrew ecosystem, and it seems certain the reborn Commodore itself will be launching software designed to take advantage of features like the REU, most buyers will probably be more interested in compatibility with the four decades of software and hardware released since the Commodore 64's original launch.

Unlike emulation-based devices, such as TheC64 and TheC64 Mini from Retro Games Limited, the C64U is a ground-up gate-level recreation. Those ports on the back aren't just for show: you can connect almost anything designed for an original Commodore 64 to the C64U and expect it to work, with Commodore itself claiming "99% compatibility" for cartridge-based devices.

To put Commodore's compatibility claims to the test, the review sample was connected to a wealth of hardware new and old. Its IEC serial port was linked to Commodore 1570 and 1571 floppy drives and a VIC-1520 four-color plotter, none of which caused it even the slightest difficulty. A range of joysticks were used on the nine-pin ports at the side, again without problem. Support for serial-connected printers, meanwhile, is in-the-works, with a firmware update due to land some time next year.

The "Memory Expansion" port, meanwhile, got the heaviest workout. A selection of commercial games cartridges produced when the Commodore 64 was new for the first time worked without a hitch. A Datel Action Replay VI cartridge was a trickier test, offering features like freezing running software, modifying memory, extracting and editing sprites, and a fast loader to speed up disk operations — all of which worked just fine on the C64U, as did modern Epyx Fast Load Reloaded and Easy Flash cartridges.

The next test was Simons' BASIC, a cartridge-based expansion to the Commodore BASIC 2.0 language included on the Commodore 64's built-in ROM written in 1983 by then-16-year-old developer David Simons. This, too ran without difficulty, as did, perhaps surprisingly, a Commodore Communications Modem designed to connect a Commodore 64 to a telephone line and out to the Compunet online service.

The only thing in the pile of test hardware that gave the C64U even a moment's trouble was the Commodore SFX FM Sound Expander, a not-terribly-well-selling add-on that provides FM sound synthesis capabilities plus the ability to hook up a full piano-style keyboard or to use the built-in keyboard with or without plastic toy piano overlay for musical purposes.

At default settings, the Sound Expander produced no sound at all — the result, Zweijtzer diagnosed over email, of the C64U sending all signals to its virtual internal "cartridge," used when loading CRT-format cartridge images from storage, unless it sees a ROM connected, which the Sound Expander lacks. Toggling the cartridge mode to focus on external cartridges even if there's no external ROM present fixed this, and the Sound Expander was soon happily playing away.

The final hardware tested with the C64U was a Commodore 1530 Datasette tape drive, a must-have for anyone who has built up a collection of games on cassette over the decades. This too worked perfectly, with the C64U able to control the motor to stop and restart playback for multiload tapes. Users of the Ultimate 64 on which the C64U is based have, however, noted that some titles with strong copy protection relating to motor operation may fail to load — but none of the game and software packages tested during this review showed any such incompatibilities.

For all but the most esoteric software and hardware, it seems clear that compatibility isn't going to be a problem for the C64U.

The new stuff

If all you wanted to do was play your old games, though, you could pick up a refurbished original Commodore 64 or even just fire up one of the many open-source emulators around. The C64U is something new, which means it bring some modern niceties along for the ride.

First among these is it ability to handle disk and tape images. These can be loaded from USB storage — the machine is bundled with a 64GB USB stick pre-loaded with over 100 games, utilities, demos, and music collections, disguised as a cassette and labeled "The Very Second" in reference to "The Very First" tape bundled with the original C64 — or a microSD Card installed in an internal slot.

Loading software from a disk image surprises with a simulated drive sound, linked to the actual read/write operations and played back over an internal speaker. Tape images, and real cassettes, if you have a Datasette connected, cause the speaker to play back the data as an audio representation — a somewhat unpleasant screeching that you can, thankfully, turn off.

If you have a real disk or tape drive connected you can use these in place of the emulated drives, and you can even capture the contents of physical media into disk and tape images, to save them from bit-rot. A quick trip to the menu lets you create blank disks, too, for saving files — like this review, the first draft of which was written in Mini Office II on the C64U.

The C64U's Wi-Fi and Ethernet networking isn't just for show. Enabling the built-in FTP server lets you access all the various storage options on the C64U, making it easy to add new disk or tape images. A web interface allows you to access an assembly monitor, directly boot PRG or CRT files, paste and edit BASIC programs, bring up the system menu, and reboot the machine, as well as play SID files through the FPGA's pleasingly-convincing recreated Sound Interface Devices or actual physical SID chips salvaged from otherwise irreparable Commodore 64 motherboard.

Bundled communications software allows you to use the network connections to "dial-up" to bulletin board systems (BBSes), and to access the Commoserve file server to stream disk images for immediate use — the latter of which will be used to distribute one of the bundled games, which at the time of writing hadn't quite been finished. It's even possible to stream debugging information over the network, a handy feature for developers, while older software can access the network via modem emulation.

We're still not done: the C64U can emulate a number of different printer models, which appear to the system and any running software as a physically-connected printer. Both images and text can be "printed" to a PNG file on any storage device, while text can be "printed" to an ASCII-format text file for use in modern software; either can be saved as a raw data stream for use with an emulator or other software. A word of warning, though: attempts to print this admittedly lengthy review to PNG failed catastrophically, with the system freezing entirely; printing to ASCII, thankfully, worked fine. Either way: always save before printing!

Some of the new features unlock capabilities that go beyond simply emulating what was possible in the 1980s. The MOS 6510 processor core running on the FPGA, for example, can be overclocked to run at speed of up to 64MHz, a major boost over the original roughly-1MHz clock speed of a classic Commodore 64. It's also possible to use multiple SID chips, the component responsible for the Commodore 64's iconic sound: as well as the two sockets on the motherboard for original chips, you can configure anywhere up to eight of the FPGA recreations to run side-by-side — used by one of the bundled demos to incredible effect.

Other features are more subtle: like the original Commodore 64, the C64U doesn't come with a bundled joystick, and if you don't have one to hand you could find yourself locked out of the majority of games and other software available to you. A quick trip to the menu allows you to enable keyboard joystick emulation, turning the WASD cluster and Return into a joystick equivalent — and while you're in there you can swap the joystick ports around, for when you've plugged a physical joystick into port two but the game expects it in port one.

A final mention must be given to the manual. Inspired by the original User's Guide, the spiral-bound book bundled with every C64U is considerably thicker thanks to a lengthy introduction to Commodore BASIC as part of Simpson's positioning of the reborn company as dedicated to "friendly computing." It doesn't cover things to quite the level of the original Programmer's Reference Guide, but it does a great job of introducing newcomers to what a Commodore can do besides games.

Conclusion

Is the Commodore 64 Ultimate a real Commodore 64? You won't find any MOS chips inside, and purists will likely scoff at the idea that even the best FPGA recreation could come close to the iconic sound of Bob Yannes' 6581 — though, for these, there's always the option of fitting a real SID chip or two.

It's not an emulator like RGL's TheC64, offering far broader compatibility with both software and hardware coupled with far more accurate performance. It's been designed and built with love, and with respect for what made the Commodore 64 such a special machine, but while admitting there are modern technologies that can make it even better.

The death of Commodore saw the brand and its properties scattered to the wind, and Simpson will have a long road ahead if he's planning on gathering all that back into a One True Commodore. This goes double if he wants to walk in the original Commodore's footsteps and follow up with a new Amiga, the rights for which are fragmented and the focus of considerable friction.

Whether or not you accept the new Commodore as a true rebirth of the original, the Commodore 64 Ultimate is an impressive device. It's accessible to the newcomer, though be sure to pick up a nine-pin joystick or two if you don't already have one, and offers near-total compatibility for the Commodore collector along with the potential to preserve the contents of any tapes and disks you have lying around when paired with suitable drives. It's attractive, robust, and happy to work with modern HDMI and DVI displays as well as classic CRT TVs and monitor.

At $299.99, rising to $349.99 in the new year, it'll set you back more than a refurbished original C64, but you're getting much more than Commodore was putting in boxes back in the 1980s. If you want something a little more eye-catching, the Starlight Edition pairs a wealth of RGB LEDs with a transparent case and keyboard at $349.99 ($399.99 next year), while the limited-production Founders Edition tops the range at $499.99 ($549.99 next year) in golden hues.

The C64U isn't perfect. The promise of "N-key rollover" in which there are "no inputs missed" regardless of how many keys you hold down is over-egged in the marketing material, as the way the C64 kernal scans the keyboard matrix makes this an impossibility — and even typing a bit too quickly can result in dropped inputs, as numerous hopefully-now-corrected instances of "Commodor" in this review demonstrated. That behavior, at least matches an original C64, so it's more a mark against Commodore's marketing than the capabilities of the machine itself. To list a few other gripes: considering the 128MB of memory on board it's surprising there's no option to run the C64U in Commodore 128 mode, the emulated printer could do with a polish so it doesn't crash on long documents like this, and it'd be nice for a fast load cartridge ROM to be included on the bundled USB stick to cut down on loading times.

If we're honest with ourselves, though, the Commodore 64 wasn't perfect either, as anyone watching data slowly crawl from a 1570 disk drive, which ran at a fraction of its planned speed thanks to a last-minute compatibility bug worked around in software, will attest.

If you're a Commodore fan, the Commodore 64 Ultimate will deliver. If you're new to the C64, it'll get you started with a lot less fuss than trawling the auction sites for original hardware. And if this is what the reborn Commodore has to offer as its first commercial product, I can't wait to see what's next.

The Commodore 64 Ultimate is now available to order on www.commodore.net.