SNES Console Revision Differences. SHVC-CPU-01 vs 1CHIP-Mini

[SNES_is_the_Best]

In 1995, Nintendo - in an effort to cut costs - did a major revision to their SNES. They consolidated their CPU, PPU1, and PPU2 into 1 Single Chip, known as the "1CHIP", and they also consolidated their Multi-Chip APU (audio processing unit) into 1 Single Chip.

Performance wise, things changed, and the following list will do its best to point out what those changes are (for the sake of convenience, I'm not going to list the several minor revisions prior to the 1CHIP. They are extremely minor and - other than the video encoder - show virtually no difference to the SHVC-CPU-01)

Before I begin, allow me to clear up the confusion regarding the 1CHIP SNES, and the SNES Mini (or SNES Jr.) Many people believe that these are different. But in fact, they are virtually the same (minus cosmetics). The SNES Mini uses the same guts, chips, etc as the 1CHIP SNES. The CPU/PPU is the same, the RAM is the same, the Audio Unit (APU) is the same. The PCB is smaller, the shell is redesigned, and S-Video and RGB are not hooked up, that's all. (for evidence, click ---> here and scroll down a little)

Ok, lets discover the differences!


Difference #1 - Games Performing Inaccurately - The revised SNES is, according to Byuu (author of BSNES/Higan)

honestly more of a clone system. There are "drastic" changes. Not so much stuff that's going to affect most games directly, but stuff that tells you the chip is radically different on the inside. Things like the SMP Timer Glitch vanishing, different behaviors of the TEST register, some DSP subtleties, the PPU being entirely different, and mid-scanline effects are totally different which affects games like A.S.P. Air Strike Patrol where the plane's shadow is almost invisible.

I can concur. Are other games affected? Yes. How many? I don't know. But.......

DISCLAIMER: The following list of games IS NOT finished. I have not done any exhaustive testing (that would take YEARS). But so far, I've "accidentally" stumbled across the following........

-- Rudra No Hihou/Treasure of the Rudras (the top left and right edges of text/conversation boxes are slightly warped and/or glitchy)
-- Disney's Aladdin (visual glitches at the top of screen, go to stage 1 to see)
-- Demon's Crest (visual glitches at the top of the screen, go to stage 1 to see)
-- Final Fantasy Mystic Quest (visual glitches at the top of Title Screen)
-- Super Ghouls N' Ghosts (visual glitches at top of screen in stage 2 when climbing ladder(s) on boat. There may be more, haven't done much testing)
-- Game Genie (not really a game, but Version 1.0 doesn't work at all. Version 2.0 does, but only lines 1 & 5)
-- Air Strike Patrol (I didn't accidentally stumble on this one, but I did test it to verify what Byuu said, and he's right. The plane's shadow is virtually invisible)
-- Magical Pop'N (Very hard to spot and minor, but random white dots appear on screen infrequently. Reported ---> here )
-- Soul Blazer (the revised sound unit doesn't seem to function identically. In Soul Blazer, you'll notice that the opening music lags badly. Now on earlier consoles, this would occur as well, but it would be easily corrected with hitting "Reset" or the next time you turned on your console. But on the revised "S-APU" audio chip, the "Reset" trick no longer works. And on a side note, my SHVC-CPU-01 never shows any lag with the opening song. Just makes me wonder what other games are negatively effected by the revised audio unit)

Its also been reported that some games run slower. Apparently the revised CPU is weaker/slower. Here's what's been found thus far.
-- Star Fox (Reported ---> here - )
-- Doom (Reported ---> here - )

Again, I have not done any extensive testing. For this to happen, I would have to literally play through the entire library of SNES games. So all I can report is what I've accidentally stumbled across, or what others have found. As of right now, I'm not sure as to "why" these issues occur or if there is a fix for them.


Difference #2 - Ghosting - UNLESS your display (and/or scaler, converter, etc) has a sufficient noise filter, then you'll notice that the output of the 1CHIP-Mini has a flaw that results in "shadow ghosting". This means that you'll see faint shadows/noise that extends to the right of objects on screen against bright blue, or bright green, or white or gray backgrounds. Its highly annoying and very noticeable on every 1CHIP-Mini that I've used.

The easiest way to spot is with Yoshi's Island. Go to Stage 1-1, and place Yoshi against the bright blue/white sky and jump around. If your display/scaler isn't filtering your signal, then you'll see shadows to the right of Yoshi (the SNES Mini that I tested has 3 shadows extending towards the right of Yoshi).

How to get reduce it? Well, if your TV set has DNR (digital noise reduction) then it will reduce it (I was able to get rid of 70% of the ghosting on both a 1CHIP-03 and a SNS-Mini that I tested on my Pioneer Plasma). XRGB units also filter and process the signal so they will reduce it as well. WARNING: Using DNR may possibly increase or add input lag as its a form of digital processing, and your mileage may vary depending on how laggy your HDTV already is. Also, the XRGB-Mini has 24ms of input lag, so be warned. (I personally use Standard Definition CRT's that don't have DNR, so I can easily see the ghosting)


Difference #3 - Reduced (?) Vertical Bar - The vertical bar tends to be less noticeable on the 1CHIP-Mini, but unfortunately, it still exists (a quick example is a 1CHIP-01 that I tested. The vertical bar on it was 2-3 times more noticeable than my original SHVC-CPU-01)

Now vertical bar visibility DOES vary among all SNES consoles. Its not visible on some, while it is on others. But so far, I've been able to see it on every single SNES console I've gotten my hands on (new or old). So the idea that it does not exist "at all" on the Revised SNES is misinformation. I will however say that the 1CHIP-03 (not 01 or 02) has the least visible Vertical Bar out of all SNES's that I've seen.

But why do some says it invisible on the Mini? Well, it COULD possibly be that the revised PCB is less noisy. But it could also be the RGB-Modding. For example, when RGB-Modding a SNES Mini, its common bypass the encoder with an amplifier, and this reduces the vertical bar visibility. But guess what? You can do the same thing with the original SNES, and achieve virtually the same results.


Difference #4 - Overdriven Whites - The 1CHIP-Mini runs on the hot side in regards to white level. You'll easily notice this right away when comparing it to the original SNES consoles, or other consoles (if just measuring white level). This actually makes some pixels stand out more than others, which can make them appear to be sharper, but it can also be very abrasive as well, depending on the game, display, etc.

While you can clearly see the difference right away, some have went through the effort of measuring the output, and found that it does indeed run on the hot side.


Difference #5 - Sharper Picture - As many have noticed, the 1CHIP-Mini is sharper than all other SNES revisions. While noone knows exactly why yet, its clear that the picture appears to be, well, clearer.

Why do the pre-1CHIP consoles have a softer picture? Well its due to Color Bleed. You might be thinking "What, even via RGB"? Well the answer is, yes. Many have noticed how the colors of pixels bleed to the right, and this is what's making the picture look softer (some call it ghosting, but its not the same thing. Ghosting is "signal reflections" and is not innate to the PPU)

While the reason for the pixel bleeding is currently unknown, its possible that the DAC (Digital-to-Analog Converter) is causing the distortion. It could also be the transistors after PPU2 (or a combination of the DAC and Transistors). I myself use to believe that Nintendo intentionally added mild bleeding for the purpose of blending dithered patterns, but I honestly do not know for sure (Side Note: Sega's Genesis has pretty poor Composite output, which caused massive color bleed. They took advantage of this by using tons of dithering, which would create new colors and fake transparencies. See this link for more info).

Nevertheless, the 1CHIP-Mini SNES has picture quality issues also, which are ghosting, overdriven whites, and visual glitches with "some" games. So pick your poison.

Anyway, I hope this list helps all who read it.

NOTE: Feel free to post new games that you may find issues with on the 1CHIP-Mini. This thread is exactly for that purpose.


EDIT: SEVERAL frequent minor edits, corrections, and updates have been made, new games added to list, etc.

[ninjainspandex]

ohhh so thats what the DNR setting does on my HDTV! I always turned it off because it added horrible input lag with no visible difference in picture clarity. When it was turned off there seemed to be no noticeable input lag. Good info on all this. Though I use an arcade monitor in a box as my RGB setup and I can't notice any vertical bars when played on the monitor but I can just barely make it out on my XRGB-mini if I get real close to the screen and turn off scan lines. But it is so minor I never would of noticed it if anyone hadn't pointed it out, I have a non 1 chip regular SNES btw.

[SNES_is_the_Best]

ohhh so thats what the DNR setting does on my HDTV! I always turned it off because it added horrible input lag with no visible difference in picture clarity. When it was turned off there seemed to be no noticeable input lag. Good info on all this. Though I use an arcade monitor in a box as my RGB setup and I can't notice any vertical bars when played on the monitor but I can just barely make it out on my XRGB-mini if I get real close to the screen and turn off scan lines. But it is so minor I never would of noticed it if anyone hadn't pointed it out, I have a non 1 chip regular SNES btw.

Yep. I'd imagine that the DNR might even reduce the vertical line a little, not sure though, as I've only ran the test with the ghosting issue because the vertical line was not as bad as the ghosting. But still, DNR is virtually useless (for games) cause of the hideous input lag added, which your already well aware of.

Speaking of your XRGB-Mini, here's a picture of the original SHVC-CPU-01 hooked up to one (obviously I'm not referring to the MegaDrive/MasterSystem photo's beneath it)

As you can see, the pic with scanlines turned on is very sharp. Again, this is the launch model SNES, and honestly, I don't see how anyone could look at that pic and claim "that's so blurry!". IMO, that would be simply dishonest. It looks very crisp.

As an interesting side note, I've been told by the guy who took that very pic, that the official SNES RGB cable is essentially required for the SHVC-CPU-01. He stated that the original SNES is very sensitive to noise IF each line on the cable is not properly shielded. I can verify that - with the Official SNES RGB-21 cable - each individual line are separately shielded AND grounded (yep, that's right. Red has its own shield, Green has its own shield, and likewise Blue, Sync, and L/R audio). So its probably not wise to use a custom, hand-made, or aftermarket RGB cable in this instance.

[ninjainspandex]

ah yes I forgot about the shielding on the scart cables, I made the mistake of buying the cheapest scart cable I could find on ebay. But it gave this bad buzzing noise whenever the screen gets very bright. So after that I bought a scart cable from a reputable cable maker on ebay who states her cables are properly shielded, which they were no more buzzing. Though I was able to use that cheap scart cable with my RGB modded N64 and it doesn't have the buzzing issue with it so it worked out.

[SNES_is_the_Best]

I bought a scart cable from a reputable cable maker on ebay who states her cables are properly shielded, which they were no more buzzing.

I know who your talking about. Her cables are good. I myself bought one. But compared to the Official SNES Cable, there is a big difference. No multi-coax design unfortunately (ie; each individual wire separately shielded). Hope it works for you regardless.

[ninjainspandex]

I bought a scart cable from a reputable cable maker on ebay who states her cables are properly shielded, which they were no more buzzing.

I know who your talking about. Her cables are good. I myself bought one. But compared to the Official SNES Cable, there is a big difference. No multi-coax design unfortunately (ie; each individual wire separately shielded). Hope it works for you regardless.

yep her SNES cable is great! I have noticed no issues (aside from the issues that stem from the SNES itself as I stated before) and absolutely no audio buzz at all during bright screens.

[Zing]

My worst issue with the SNES Jr. is that the video output appeared to have a very high gain on it. I think this is probably part of what causes the ghosting. The whites were so strong, far too strong. I only tried it with the default composite signal, so I'm not sure if this is a fault with the composite encoder or the raw signal itself.

I'm using the original revision SNES, which seems to have relatively poor composite output, but looks fine with s-video.

[SNES_is_the_Best]

I'm using the original revision SNES, which seems to have relatively poor composite output, but looks fine with s-video.

Yours doesn't have the S-ENC encoder right? The early SHVC has the BA6592F, while the later SHVC has the S-ENC (numbers vary). The composite is noticeably better on the S-ENC (although not huge in some cases). But the S-Video is very close between the two. I have both versions (with and without S-ENC) and I can say you'll be very happy with S-Video, especially if your using the official cable.

[darcagn]

Speaking of your XRGB-Mini, here's a picture of the original SHVC-CPU-01 hooked up to one (obviously I'm not referring to the MegaDrive/MasterSystem photo's beneath it)

As you can see, the pic with scanlines turned on is very sharp. Again, this is the launch model SNES, and honestly, I don't see how anyone could look at that pic and claim "that's so blurry!". IMO, that would be simply dishonest. It looks very crisp.

I find it really odd that you flat out ignore the shadows/bleeding on that image. The top image is obviously Super Mario World on the SNES, and in both pictures, to the right side of Mario and the blocks you can clearly see bleeding/shadows. The middle and bottom images of the MegaDrive and PC Engine games through the same upscaler on the same display clearly don't have that problem.

In addition, during your research on this I provided you with both photographs and direct capture images of the 1CHIP-03 model showing no shadows or middle band with and without the Framemeister and DNR always turned off on both TV and Framemeister. But you didn't mention this at all in your post?

I'm not knighting for the 1CHIP model, if you like the SHVC better, more power to ya... but don't spread misinformation and say that all units perform one way or another.

[SNES_is_the_Best]

I find it really odd that you flat out ignore the shadows/bleeding on that image. The top image is obviously Super Mario World on the SNES, and in both pictures, to the right side of Mario and the blocks you can clearly see bleeding/shadows. The middle and bottom images of the MegaDrive and PC Engine games through the same upscaler on the same display clearly don't have that problem.

I didn't think I needed to mention it.

Why?

Because that nearly invisible "bleeding" on the right side of pixels that your referring to IS what causes the softer picture. And I've already mentioned in my post about the SNES having a softer picture.

Nevertheless, I think you pointed out something that I should have clarified. So for the sake of a misunderstanding, I've revised my statement and mentioned that the smearing is what causes the softer picture. Thanks!

In addition, during your research on this I provided you with both photographs and direct capture images of the 1CHIP-03 model showing no shadows or middle band with and without the Framemeister and DNR always turned off on both TV and Framemeister. But you didn't mention this at all in your post?

After further investigation and testing, I've learned that its impossible to capture the ghosting via "still" pictures, nor can it be captured when the game is paused. Its noise within the output of the console and thus very difficult to capture. Plus, others with a 1CHIP-03 told me that it has ghosting. And guess what? I recently picked up a 1CHIP-03 to finally settle the question, and I can confirm that it has ghosting equal to, or worse than all 1CHIP-Mini's that I've tested. There's nothing magical nor very different about the 1CHIP-03 vs. the 01, the 02, or the Mini. And why should there be? They all use the same CPU, PPU, RAM, APU, etc. Oh, and yes, the 1CHIP-03 has the Vertical Bar. I will however admit that its less pronounced than any other SNES that I've witnessed thus far.

I'm not knighting for the 1CHIP model, if you like the SHVC better, more power to ya... but don't spread misinformation and say that all units perform one way or another.

None of this is misinformation. I made it very clear that "some" TVs, or scalers will filter out ghosting, heck I frequently refurbish and sell retro consoles/games on eBay and I've tested various SNES's (SHVC, GPM, RGB, APU, 1CHIP, Mini) and the results are the same every time. I'd tried to make it very, crystal clear in my post that some TVs/scalers/etc will filter it.