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Emulating PSP cpu at 333mhz and 64mb slim ram question. - Printable Version

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Emulating PSP cpu at 333mhz and 64mb slim ram question. - BubblegumBalloon - 03-18-2013 10:00 PM

Would emulating the PSP CPU at 333mhz and the 64mb of slim RAM increase or decrease performance? I assume emulating more powerful hardware would decrease the frame rate?


RE: Emulating PSP cpu at 333mhz and 64mb slim ram question. - Henrik - 03-18-2013 10:06 PM

We already emulate the PSP CPU at 333mhz (instead of the stock 222Mhz) in the games that ask for it.

As for adding the extra RAM, I don't expect a difference in speed at all.


RE: Emulating PSP cpu at 333mhz and 64mb slim ram question. - BubblegumBalloon - 03-18-2013 10:26 PM

Thanks for the answer! I didnt know that PPSSPP was already emulating the cpu up to 333mhz.

I didnt know the PSP increased its clockspeed for some games, I always assumed it ran at 222mhz unless it was changed using a modified version of the OS.

And as far as I know the only thing the PSP needs 64mb of ram for is Skype.


RE: Emulating PSP cpu at 333mhz and 64mb slim ram question. - VIRGIN KLM - 03-18-2013 11:49 PM

(03-18-2013 10:06 PM)Henrik Wrote:  We already emulate the PSP CPU at 333mhz (instead of the stock 222Mhz) in the games that ask for it.

As for adding the extra RAM, I don't expect a difference in speed at all.
There are games that check though the model and if it returns a 32MB model it gives 16bit colorspace with dithering and if it returns 64MB model it gives 24bit.


RE: Emulating PSP cpu at 333mhz and 64mb slim ram question. - m45t3r - 03-19-2013 04:38 PM

The PCSX2 emulator allows you to run at a arbitrary CPU speed. If you set a lower CPU Speed than the official PS2 sometimes this gives a performance boost since there are less cycles to process (of course, the game should be low on CPU utilization or it will have the opposite effect).

I don't know if the same thing would be useful to PPSSPP since the whole emulation is HLE, but a dev would give a better explanation if this thing would work or not.


RE: Emulating PSP cpu at 333mhz and 64mb slim ram question. - Henrik - 03-19-2013 04:43 PM

It can work for games that are capable of frameskipping internally if they can't keep up, and it's something we could experiment with for sure.