Changes in version 5 NESRGB.

** Increased ease of installation.
There are only three solder jumpers on the board, down from eleven on V4. All the rest of the features/settings are detected automatically or controlled via the new on-screen menu. The board shape has been changed slightly, with a larger cutout in the lower right hand corner. Some NES motherboard versions have tall capacitors at this location. PPU location has non-plated through solder pads that can only be soldered from the bottom of the board. This makes it impossible to accidentally mix up PPU and motherboard pin rows. A FFC connector has been added which has the same pin configuration as the popular Voultar QSB board, for connecting a Nintendo-like multi-out AV socket. The power consumption of the NESRGB board has been reduced enough that the external voltage regulator is no longer provided, eliminating another point of failure.

** Better troubleshooting features for when installation goes wrong.
If an installation fails, it can be difficult to tell whether the problem is the NESRGB board or the game console itself. Now there is a user test feature which can test every part of the NESRGB board in isolation outside of the console (only powered with a +5V supply). It is possible to determine that the board is OK or not without another console. The non-plated through holes in the PPU spot makes it easy to remove a PPU soldered to the NESRGB board with just a solder sucker or solder wick. There is also a monitor mode that which can be used to check basic system function on the LEDs while the system is running.

** Improved audio circuit.
Now it properly supports for cartridge audio mixing on both NES and Famicom. High gain for old Everdrive N8 flash cartridge, low gain for Everdrive N8 Pro and original Famicom cartridges. There is a setting for high gain, low gain, and mute in the on-screen menu. It no longer makes a 'pop' sound in the audio during power on/off (when using original cartridges).

** New video system.
The most significant changes in version 5 are to the video system. The video encoder IC has been removed because its power consumption is high and because nobody makes these parts in volume any more, sourcing them is becoming difficult. Generating composite video is not particularly interesting, as the console does that already. The encoder was really only being used for s-video, so I have moved that into the FPGA logic. S-video is generated the same way as the NES generates the composite video, the only difference is the luma and chroma signals are not combined at the end. This method of generating s-video does net support different palettes, but it is accurate, and you can always adjust the colour saturation on your display to suit. 

The video outputs are composite video (from the PPU), s-video (just mentioned), RGB (much the same as before), and component video, which is a new addition. RGB and component video support different palettes and there are ten different palettes to choose from:
Generated NTSC, Generated PAL (from the PALLY palette generator), Nestopia YUV, Smooth V2, Digital Prime, Pixeltao CRT, Sony CXA, Fceux, Dark Power, Playchoice. These can be selected via the on-screen menu or cycled through with a controller button combo like V4.

There is a 'load detect' feature which can be used to determine what type of cable is attached at power on and select the video output type automatically. When a multi-out AV socket is used, it can support all four video output formats by changing the cables. The low cost component video cables with the multi-out connector (found on Ebay, Amazon, etc) are supported. There is also a way to force the video output signal via the controller.

The De-jitter feature, now renamed to Sync Fix, can be turned on and off via the menu. It has been re-written for better compatibility and now allows adjusting the position of the video output by up to +/- 15 pixels horizontally and vertically.

** Backwards compatibility.
I'm currently in the process of making a completely new set of installation guides for version 5. Even if you do follow an older guide or video, you should still be able to achieve a good result. Solder jumper reference numbers are not re-used for different features, and mechanical switch palette selection still works. The audio mixing point is still there too, so it's possible to do cartridge audio mixing like older NESRGB versions of you really want to.