Hi everyone!
What you are about to see here may look like your typical run-of-the-mil American toaster NES:
(http://usuarios.lycos.es/dogbert/ocnes/toasternes.jpg)
But a closer inspection to the underside...
(http://usuarios.lycos.es/dogbert/ocnes/speedsw.jpg)
Yup, it's overclocked!
Overclocking your NES is easy: You just have to cut the CPU clock pin and feed it the clock of your choice, but 12X the clock speed you want. For example, the NES generates a 21.47727MHz clock signal for its CPU and PPU, which gets divided by 12 by them internally yielding a 1.79MHz effective clock speed. So to make it run at 2.0MHz you have to feed it a 24MHz clock signal.
What is the benefit of overclocking it? Does it make your games run faster? No, like overclocking your computer, it boosts the CPU's processing power, getting rid of the annoying slowdowns you get in so many games for example, when you get too many enemies onscreen at a time. Now you are playing with POWER! ;D
Not all NESs overclock the same, some can take higher speeds than others. Too high of a clock speed and you get massive glitching all over the screen and crashes (Note: You can't overclock the PPU, doing it will raise the video output above 60Hz, rendering it useless for TV display). You have to try different clock speeds until you get the best for your NES. I tried about 6 speeds, from 1,3MHz (that's actually underclocking it :P) to 3,75MHz! and found 28.3220MHz (or 2.36MHz) to be the most stable and glitch-free. A good source of TTL crystal clock generators are old computer motherboards and add-on cards. I got mine from an old ISA video card ;)
A little downside of the overclocking is that since the sound generator is inside the CPU, raising the clock speed will raise the sound pitch as well (I actually find that pretty funny, the dog barking in Duck Hunt sounds like some tiny poodle :D).
I installed a switch below the unit to switch from the stock speed to the overclocked speed (below the unit to avoid ruining the aesthetics of the system). Here's how it's all connected:
(http://usuarios.lycos.es/dogbert/ocnes/clocksw.jpg)
The clock generator takes 5V from the output pin of the voltage regulator, and a ground (I used the RF shield as a ground point). The switch lets me select between the original clock (taken from the PPU clock pin) and the new clock. Use the thinnest and shortest cables you can to maintain the signal quality.
Here the wiring is nicely routed and the clock generator glued to the case with a little hot glue.
(http://usuarios.lycos.es/dogbert/ocnes/readytogo.jpg)
When I get my TV capture card working properly I will upload some comparison videos to my Youtube account so you can see the difference between speeds.
Comments? Questions? Suggestions? I'll be glad to hear them!
Now that's awesome.
What games does it noticeablly speed up?
good stuff
Awesome information. I hadn't heard about this before. It'd be neat to see something like that for the Famicom.
Judging by the mainboard pictures I've seen of the Famicom, it is technically possible (it uses the same Ricoh 2A03 CPU with the same pinout). I know you guys can recall many times you get massive slowdowns in NES games ;D. The only thing that crosses my head right now is sometimes in Megaman 3 with some enemies that spawn another enemies and in Super Mario Bros 3 when there are lots of goombas. I'm testing my game collection and picking some examples ;).
P.S:Famiclones with NES-on-a-chip gloptops are not overclockable, since the CPU and PPU share the same gloptop there's no way to selectively overclock the CPU while keeping the PPU on stock speed. Replacing the crystal oscillator on these will overclock both units and render the video output useless.
I always have problems with shooters, especially Life Force. I bet Recca would be similar because of all the shit on the screen at one time. I might have to try this sometime soon. I'm not very good with modifications, but we'll see...
Try the 4th stage of Gradius II. ;)
Spent all afternoon trying to make my TV capture card work (it suddenly began recording full of video glitches - tried reinstalling its drivers, updating them, moving it to another PCI slot, reinstalling video card drivers, replacing the monitor (!) to no avail). Luckily it now looks less shitty than before (kinda decent), so I recorded a short video testing SMB3 overclocked! The slowdown is not as massive as in another games, but it's the easiest to film. Try it!
Video http://www.youtube.com/watch?v=g4m-wyFC5-M (http://www.youtube.com/watch?v=g4m-wyFC5-M)
I'll be uploading more soon!
That's cool man! ;D Will you write a step by step guide on how to do this?
Yup, I'm waiting for my sister to return my digital camera ;D
I'm not exactly what you'd call techinically minded...would you consider modding my own NES if I mailed it to you? How much would you want for that?
Wouldn't shipping a thing the size and weight (think the RF shielding!) of an NES from Ontario, Canada to Santiago, Chile cost a small fortune? You'd have to pay shipping both ways and I have to see if I have an appropriate clock generator (or you can send one of the desired frequency). As for how much I want... I think an interesting NES/Famicom cart inside the NES would be great ;D
Try the fourth stage of Gradius II. :)
I don't have Gradius II, sorry ::)
Quote from: JC on June 23, 2007, 09:34:10 am
I always have problems with shooters, especially Life Force. I bet Recca would be similar because of all the shit on the screen at one time. I might have to try this sometime soon. I'm not very good with modifications, but we'll see...
Recca is a true humiliation!
There are plenty of sprites and almost no slo-mo!
What about Parodius?!
133MHz!!!
Does the overclock alter the sounds too much?
Depends on how much you alter the clock speed, but I don't think it is an issue. You can check my Youtube video above to hear the difference.
Also, if anyone is interested, I have 2,09MHz, 2,50MHz, 2,61MHz and 2,82MHz speeds in stock, if someone wants me to mod his/her NES
A step-by-step guide is on the way too! ;D
Mmmm...
Very good!
The difference is noticeable, and the sound is great!
But what are those glitches?
Are those because of the recording or due to the mod?
It's my shitty 30 bucks TV tuner card (it looked worse, that's the best I could get of it).
Quote from: 133MHz on July 03, 2007, 01:34:47 pm
It's my shitty 30 bucks TV tuner card (it looked worse, that's the best I could get of it).
OK!
I will try that later!
Some of the better shooting games have this slo-mo
sickness! I think that it would be great to play them
again at full speed!! :D
Especially Parodius!
another parodius fan on the forum? amazing
Quote from: kite200 on July 06, 2007, 06:56:50 pm
another parodius fan on the forum? amazing
Well, my choice was Parodius because the slow down
alter the gameplay too much for me!
But yes, I do like all the Parodius games!
I even bought the Paro Wars PSX game!
must overclock....
Quote from: kite200 on July 06, 2007, 06:56:50 pm
another parodius fan on the forum? amazing
I breathe Parodius. I own the Famicom game and the 3 Super Famicom games! Got to grab a Saturn for Sexy Parodius.
Hey 133MHz, could you possibly make a video playing Megaman 2 (Metal Man's stage) on overclocked NES? that whole section is plauged by sprite flickering, and I want to see just how good the overclocked NES is at handling the flicker.
Quote from: kite200 on July 06, 2007, 06:56:50 pm
another parodius fan on the forum? amazing
I love Parodius too.
The only Megaman cart I possess is Megaman 3 ^^U
This is very freaking cool. I wouldn't mind having one of these either.
~~NGD
Overclocking is a great idea especially if you have a spare system to do it on. Overclocking increases the heat on the CPU, did you add some heat sinks to the CPU to help with that? If not you could cook your CPU if you run it overclocked for too long. Look into overclocking on wikipedia if you guys want more info on the pluses and minuses of doing an overclock.
The NES Ricoh 2A03 CPU runs at a paltry 1.79 MHz, even overclocking it insanely like 4 MHz would not make it produce enough heat even to get the thing warm to the touch. The thing has like 1/100th the power of a 1992 PC ;D and those didn't even required heatsinks on their processors :P
So did you ever write that guide on how to do it? :P
Hi! I was a little busy lately with another projects and stuff, like remodelling my room (made a poor man's reprogrammable NES cartridge also). Took lots of pictures, so it's just a matter of writing. Stay tuned!
Hey 133MHz, do you think it possible to overclock an AV Famicom? I'm thinking of buying another one, and would defenetley get you to do it if at all possible. Do you think it would be sagnificently different/more difficult than the big boxy NES?
Totally possible. Only the NOAC based Famiclones are not overclockable (since CPU & PPU share the same die)
Alright, so the AV Famicom came in the mail today! It'll cost me $28 bucks to ship it by air in a little over two weeks. I'd do it as soon as I get paid. Thanks again 133MHz, I can't wait for your tutorial.
Wow, you got a pretty good shipping deal! money and time-wise ;D
Hey just out of curiosity, has the av famicom I sent you arrived yet? If not it should be within the next few days.
Nope, it hasn't arrived yet.
;D ;D ;D ;D
The overclocked AV Famicom arrived! It works great! 200% satisfied! Now you gotta get around to writing a walkthrough :P
hey 133MHzz wheres the clock pin on the nes processor what number is it and on what side is it on (left or right) ???
Pin 29 is the Clock Input pin. Use the notch on the chip to guide yourself.
_____ _____
| \_/ |
SND1 - | 01 40 | - +5V (Vcc)
SND2 - | 02 39 | - STROBE (joypad)
/RST - | 03 38 | - EXT 44
A0 - | 04 37 | - EXT 45
A1 - | 05 36 | - /OE (joypad 0)
A2 - | 06 35 | - /OE (joypad 1)
A3 - | 07 34 | - R/W
A4 - | 08 33 | - /NMI
A5 - | 09 32 | - /IRQ
A6 - | 10 31 | - M2
A7 - | 11 30 | - GND*
A8 - | 12 29 | - CLK
A9 - | 13 28 | - D0
A10 - | 14 27 | - D1
A11 - | 15 26 | - D2
A12 - | 16 25 | - D3
A13 - | 17 24 | - D4
A14 - | 18 23 | - D5
A15 - | 19 22 | - D6
GND - | 20 21 | - D7
|_____________|
hey how can i power the clock generator? can i do it with the voltage on the processor
Yes, you can use the +5V and GND pins from the processor to power the clock generator, or in fact, any place where you could find them (like the voltage regulator, controller ports, or other chips).
What oscillator frequency will you use? And where did you get (or plan to get) your clock generator?
its at 46.something Mhz and i think its out of a video card
That would yield a CPU frequency of ~3.8 MHz which is quite a lot but some consoles can take it. Good luck!
As when overclocking PCs, some CPUs can run higher than others and the only way to know is through experimentation ;).
can the nes take it
Mine crashed over 2.5 MHz, but satoshi's console would take way over 3 MHz and still run perfectly.
The only way to find out is by testing.
Would this make the Megaman series flicker/slow down less?
It will help the slowdown. It will not help the flickering.
Is the flickering done by hardware or is it programmed into the games?
It's because of the graphics..so I guess I'd say it'd be the hardware not being able to handle the sprites.
The flickering isn't programmed by purpose.
The Famicom is only able to handle a certain number of sprites in one line. If that number is exceeded, the sprites start to flicker.
Quote from: Blue Protoman on June 16, 2009, 07:10:23 pm
Is the flickering done by hardware or is it programmed into the games?
Programmed into the games.
Like manual said, the FC/NES can only handle 8 sprites per scanline. More than that and the graphics become unpredictable (if it even lets you do it...I forget the details). There's a register that gets set when this happens. It's up to the software to check this register and act accordingly (ie, toggle/flicker the sprites to give the illusion of more than 8 sprites per scanline).