"The TI-84 Plus Silver Edition was released in 2004 as an upgrade to the TI-83 Plus Silver Edition. Like the TI-83 Plus Silver Edition, it features a 15 MHz Zilog Z80 processor, 24 kB user available RAM (the actual chip is 128 kB, but TI has yet to code support for the entire RAM into an OS), and 1.5 MB Flash ROM. Like the standard TI-84 Plus, the Silver Edition includes a built-in USB port, a built-in clock, and assembly support. It uses 4 AAA batteries and a backup button cell battery. If you take out the batteries while the TI-84 is running, it clears the RAM. TI offers yellow versions of this calculator to schools. Owners can buy other interchangeable colored face-plates and slide-cases online. A kickstand-style slide case and other accessories are also available. The TI-84 Plus Silver Edition comes preloaded with a variety of programs, including App4Math, an interface upgrade that allows students to input math problems exactly as they appear in the textbook."

Wikipedia
http://en.wikipedia.org/wiki/TI-84_Plus_series

did anyone ever managed to use this/figured out how you could use this?
Or is the chance we'll ever be able to use it 0,0% .

crap

If you knew ASM and had a project that needed it, you could write a program that would take advantage of all that RAM. But I suppose that's not the question being asked.

One of the problems of a new OS that claims compatibility with old programs and yet has support for that extra RAM would have problems choking down projects that use that extra RAM as saferam. A big offender? Omnicalc and its RAM recovery function.

As far as ASM programs go, you just extend the mapping for known RAM pages to map all 8 of these pages.

plus if it was a totally new OS, it would no longer run old BASIC programs, not to mention, would the new OS even includes a on-calc BASIC-like language at all? Plus, ASM programs using TI routines wouldn't work anymore either. If switching back and forth from old to new OS is made easier, it might not split the community too much, though.

I like Noahbaby idea, though. Maybe for example, future BASIC Builder versions could support archived programs but instead of archiving them when decompressing them when running the game app, they would be loaded in the hidden RAM on 15 MHz models and it would allow more games to be compressed with BasicBuilder instead of just the ones using no archive and just RAM. The downside would be that they would become SE-only, but many large hybrid/basic games are alerady SE-only, anyway

my guess is lazzyness of the coders

Maybe they wanted to add new stuff in future OSes, but finally didn't. What would suck is if someone like Brandon decided to release a new OS taking advantage of that RAM then 1 year later TI released a new line of TI-84+ that got rid of that 128 KB additional RAM or most of it

It would probably cost them more to change the assembly to remove that extra RAM, since it's all on the same chip as the microprocessor and just about everything else except Flash.

If it costs them more money than they need, they won't do it. Simple as that.