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Is it possible to force emulate PSP with 333MHz CPU clock? Some games require this to run without lag on real PSP.

can you give us some examples?
I don't think that we need actually 333mhz to emulate. I have 100mhz, 266mhz and 333mhz as well and they all work fine.

the emulator often can't even emulate most games at full speed, so there's no point for that yet i think.

plus i don't think it'll be running speeds lower than 333, since there's really no point to emulate that. no battery to save in a pc, so no need to underclock it.

(02-18-2012, 01:40 AM)serio Wrote: [ -> ]the emulator often can't even emulate most games at full speed, so there's no point for that yet i think.

plus i don't think it'll be running speeds lower than 333, since there's really no point to emulate that. no battery to save in a pc, so no need to underclock it.

we are talking about Bus speed, not core speed I think.

(02-18-2012, 01:28 AM)freefive Wrote: [ -> ]can you give us some examples?
I don't think that we need actually 333mhz to emulate. I have 100mhz, 266mhz and 333mhz as well and they all work fine.

Yep, try the first Project Diva game, it's slow whether you ran it on Phenom or i7 2600K@4.5 or the Sandy Bridge-E (personally tested the first two and have friend testimony for the last).

It's a known issue on the real PSP too : http://projectdiva.wikispaces.com/messag...4#38715698

Although PJD 2nd have this problem JPCSP play the game fine, so it seems that PJD 1 just have more severe problem due to unoptimized engine I suppose.

(02-18-2012, 01:40 AM)serio Wrote: [ -> ]plus i don't think it'll be running speeds lower than 333, since there's really no point to emulate that. no battery to save in a pc, so no need to underclock it.

See the wiki above, seems the game have bug where it fail to force PSP to clock higher when it's loaded from ISO.

That's why I think maybe other laggy game could also have this same problem, and forcing the emulated psp cpu to run at high clockspeed may solve that.

Maybe some games can't be smoothly emulated by the jpcsp due to the clock problem, but I can say that it's not possible to overclock cpu using jpcsp. If you want to overclock your cpu, go to bios and set the bus speed to 333.
Yet for those cpus that are lower then 266 it's just not even possible to overclock to 333. Those overclocked sandy bridges are overclock by ratios instead of bus speed.
I have a q6600 and I can overclock it from 266 to 333, but it has no GPU so I can't test whether it will be emulated smoothly with the bus speed of 333.

P.s. I'm wondering about PSP's ratio.

I think you're mistaking thing here, see PSP has CPU which is being emulated by jpcsp, this emulated cpu is just like the real PSP cpu has standard clockspeed of 222MHz (iirc) and can clock itself dynamically from 1 to 333MHz according to wikipedia, if you ever tried CFW you'll know that you can force PSP to clock itself to its max clockspeed which result in smoother gameplay for most games but at the expense of battery life.

Afaik JPCSP is a high level emulator. It doesnt really emulate the PSPs hardware, which in case means there is no CPU you could overclock. The emulator always runs with max. speed as long as it runs at anything below 60fps.

So if your game doesnt run at full speed this just means that it uses functions that are either not yet implemented in JPCSP or just not optimized.

pcsx2 is a HLE, it can overclock and underclock EE (PS2 CPU) with various means.

Also, being a HLE doesn't mean everything is abstract to my understanding, it still need to really emulate each hardware response, just not through conventional means.

I think we need devs input to clear things up...

I dont know much about PCSX2s source code but it seems to me like it doesnt really overclock the EE either, the speedhack just changes the number of cycles the emulator waits (between execution?). You could probably do the same with jpcsp but i dont think it would solve your problem. Anyway your right, only a dev can clarify this.

EDIT: after thinking about it, serios answer should be correct, this would only effect performance if the game already runs at full speed