View Full Version : Why is the NES CPU faster in USA?
jajaja
07-09-2005, 05:01 PM
As the topic say, why do the NTSC version of NES have a faster CPU than the european NES? I know its not much, but when I play a NTSC game on my european NES the sound is slower and sometimes the games.
davidbrit2
07-09-2005, 05:16 PM
NES games usually sync to the video clock rate. NTSC runs at 60 Hz, while PAL runs at 50 Hz. So if you play a PAL game on NTSC hardware, it'll run 20% faster than it was intended, since the video clock rate is higher. Likewise, an NTSC game on PAL hardware runs at about 83% its original speed.
I'm actually not sure if the CPU runs at a different speed, though.
jajaja
07-09-2005, 05:23 PM
Ah yes.. i didnt think of that. Thats most likely the reason :) Thanks.
The CPU is alittle faster btw:
Clock Speed: 1.773447MHz (PAL) | 1.7897725MHz (NTSC)
davidbrit2
07-09-2005, 07:39 PM
Hmm, interesting. I wonder if they had to use a different base clock rate for the system to get the video clock rates where they wanted, and thus couldn't quite get the CPU clocks to match up with the appropriate multiplier.
Lothars
07-10-2005, 06:40 AM
good point that's probaly a good chance of what it is, cpu's are the same speed but just different multipliers
phreak97
07-10-2005, 10:42 AM
just thought i'd mention it's 16.667% difference, not 20%..
im picking the details here:P
Cauterize
07-10-2005, 11:20 AM
well we all know Master Systems, Megadrives & SNES's can be modded to have a 50/60hz switch...
So can a NES? as id love to mod one!!!
davidbrit2
07-10-2005, 02:08 PM
just thought i'd mention it's 16.667% difference, not 20%..
im picking the details here:P
(60 - 50)/50 = 20%
;-)
ubikuberalles
07-11-2005, 03:22 PM
just thought i'd mention it's 16.667% difference, not 20%..
im picking the details here:P
Depends on your point of view:
NTSC version is 20% faster than PAL --> (60-50)/50
PAL version is 16.67% slower than NTSC --> (60-50)/60
anagrama
07-11-2005, 03:53 PM
Just wondering, will the differing clock speed be the reason why a NES can't be modded for 50/60Hz like most other systems can be?
jajaja
07-11-2005, 06:40 PM
No idea, but I thought of a 50/60hz switch earlier for NES. Would be cool to have :)
Btw, are the antenna cables for NES also diffrent? I have a US toploader and tried it with my official NES antenna cable for my PAL NES and the picture had alot of static and no sound. I havnt tried the antenna cable that included with the top loader because I need some kind of converter for it. It doesnt fit in the antenna in on my TV.
GarrettCRW
07-11-2005, 07:08 PM
No idea, but I thought of a 50/60hz switch earlier for NES. Would be cool to have :)
Btw, are the antenna cables for NES also diffrent? I have a US toploader and tried it with my official NES antenna cable for my PAL NES and the picture had alot of static and no sound. I havnt tried the antenna cable that included with the top loader because I need some kind of converter for it. It doesnt fit in the antenna in on my TV.
It's likely an aftereffect of the differences between PAL (50Hz and 25 frames/sec) and NTSC (60Hz and 30 frames/sec). But, then again, US and Japan RF signals have the same compatibility issues, and both countries use NTSC video.
rbudrick
07-12-2005, 03:06 PM
Depends on your point of view:
NTSC version is 20% faster than PAL --> (60-50)/50
PAL version is 16.67% slower than NTSC --> (60-50)/60
Well, that's kind of playing with the numbers, but whatever. Sometimes a game is localized for the PAL areas and when played on an American system, it is 16.67% faster, since it was programmed to play the correct speed in its home country.
-Rob
googlefest1
07-12-2005, 04:24 PM
what about the clones like the NEO fami