In July 2015, a poster at the NeoGAF forums postulated something that sounded odd at the time: the PlayStation 4 has been 4K-compatible from the get-go. Even before 4K had arisen as a burgeoning standard, it was there, all along. User Jeff Rigby geeked out by analyzing things like motherboard schematics, exposed pins, and HDMI bandwidth ratings, and he concluded that everything on the hardware side was in place for a surprise 4K update. Sony just needed to push a necessary firmware update to comply with bandwidth and copy-protection standards.

That's a pretty beefy feature to leave dormant within our game consoles for so long. Crazy, right?

Apparently not: The PlayStation 4 is getting a firmware update "by next week," according to Sony Interactive Entertainment President Andrew House, to enable a brand-new visual standard on every single PlayStation 4 shipped since its 2013 launch. One that's been sleeping inside your PS4 all this time.

There's a catch, however. That updated standard isn't 4K, but HDR. While Wednesday's press conference mostly revolved around the souped-up PlayStation 4 Pro console, it also included a cursory mention of high dynamic range (HDR) compatibility coming to a whopping 40 million-plus pieces of hardware.

This could mean quite a bit for the future of PlayStation 4 as a media hub, so let's explore what's going on here and what technical roadblocks may remain.

1.4 -> 2.0 -> 2.0a

When both the PlayStation 4 and Xbox One launched in 2013, the systems' HDMI controllers were rated as HDMI 1.4. That was the primary HDMI standard at the time, and it determined how much data could be sent over HDMI cables at a given moment, which governs technical details like maximum frame rates at certain pixel resolutions.

Displaying a "full 4K" signal—also known as UHD resolution, measured at 3840x2160 pixels—is impossible via the HDMI 1.4 spec, at least at the desired 60 frames-per-second sweet spot. (4K via a 1.4 interface will work, but it's limited to 24 frames per second.) Any media-playing and computing device that wants to connect to a 4K screen via HDMI will need an HDMI controller rated at least 2.0 for those settings. The aforementioned NeoGAF forum member, Jeff Rigby, alleged that the controller was capable of that spec, in spite of its release before 2.0 had been finalized.

High dynamic range displays require just as much data throughput for so much color and luminosity data. The two leading HDR specs, HDR-10 and Dolby Vision, require no less than an "HDMI 2.0a" spec, which supplants the higher-bandwidth requirements of 2.0 with "additional metadata" required to enable the transmission/reception of such HDR content. There is no HDMI "1.4a" to offer the same boosts to HDR-ready 1080p displays. To ride the HDR train, your device better be rated HDMI 2.0a, or you're getting kicked off.

(Update: Readers have pointed out that Dolby Vision's HDMI controller requirement is lower than I originally reported. As Yoeri Geutskens points out, "Knowing that previous versions of HDMI would not pass the Dolby Vision dynamic metadata, Dolby developed a way to carry this dynamic metadata across HDMI interfaces as far back as v1.4b." That would still require a firmware update for PS4 compatibility, though not a significant boost in bandwidth requirements. However, HDR-10 is tied to the HDMI 2.0a standard.)

Rigby guessed last year that the PlayStation 4's HDMI controller is HDMI 2.0 compatible—meaning, it had been developed with higher bandwidth than the HDMI 1.4 spec required, and it just needed an official update via firmware to unlock and unleash that potential. Now, House has confirmed that it's coming, because anything rated for HDR specifications is technically also ready for 4K resolution.

One big hurdle remains (if not more)

So what's to stop the original PlayStation 4 from rendering anything at a whopping 3840x2160 pixel count? Sheer horsepower is the answer in some cases.

Even with new hardware on his side, PlayStation's Mark Cerny still had to verbally dance around the struggle to render games in 4K resolution. While he never outright stated during the Wednesday conference that the new PlayStation 4 Pro console will not render games in true 4K, he employed phrases such as "efficient rendering on 4K displays" while summing up a mix of anti-aliasing and visual processing techniques to make games look, well, less blurry on 4K displays, as opposed to a direct up-convert from 1080p.

Which is to say, if the PlayStation 4 Pro won't render games at pure 4K resolution, the weaker PlayStation 4 certainly isn't cut out for that kind of work.

What about 4K video content? That question is harder to answer, because the industry standard 4K codec, H.265, has never been advertised as having PS4 support. The Xbox One S, on the other hand, now supports 4K playback, but we know that's due in part to a brand-new HEVC decoder on its primary chip. Unless Sony has another secret chip hiding in its 2013 consoles, PS4 would have to support H.265 decoding through a makeshift software-coded solution.

Until that question is answered, it's moot to discuss HDCP 2.2, the copy-protection standard that is needed to display any UHD Blu-ray discs and other video platforms' offerings. Rigby's 2015 look at the PS4 architecture concluded that HDCP duties resided in a part of the motherboard that is firmware-updateable, but decoding is the bigger factor.

After that, there's the matter of PS4 Pro not supporting UHD Blu-ray, presumably due to licensing costs as opposed to technical hurdles. If the newer hardware won't play those discs, how the heck will Sony enable that for the older consoles?

Still, if Sony wants to continue dominating living rooms by offering consumers a preferred living-room hub, it's going to want to assert its box as a one-stop shop for every video standard imaginable. If software solutions can flip a switch for 4K streaming video on the original PS4, then it's hard to imagine Sony passing on the opportunity. Thanks to HDMI 2.0a compatibility, we know that Sony is just one step away (albeit possibly a huge one) from giving gamers a pretty astounding hidden feature on the cheap.