PSP Wi-Fi Impairs Processor Speed

GameDaily reports that the PlayStation Portable has an interesting restriction: its full processor power cannot be utilized at the same time as its WiFi functionality. Therefore, games that are played online cannot make use of the chip's 333mhz processor speed. The original finding from Beyond 3D was confirmed to GameDaily by Sony. Dave Karraker, Sr. Director, Corporate Communications: "The recent firmware upgrade (3.50) that removed the restriction on the PSP's CPU speed enables developers to utilize speeds either lower or higher than the default 222MHz, up to the full 333MHz clock speed. The article is correct that increased CPU speed cannot be used with the PSP's wireless feature." Though speculation is that this is a power-saving decision, there has been no official announcement as to the root cause.

Comments

ummm... root cause....

[Fallen Kell]

Though speculation is that this is a power-saving decision, there has been no official announcement as to the root cause.

I would think that the root cause would be the network stack and packet processing overhead that occurs when the item is networked... but I am just thinking like an engineer here...

Re:ummm... root cause....

[MeanMF]

Processing overhead would explan reduced game performance, but not the need for a lower clock speed.

Re:ummm... root cause....

[Joe The Dragon]

or it maybe that when the cpu is running at 333 the system bus is running to fast for the wi-fi chip like how when you overclock the FSB on older MB's the pci bus and other buses speed up as well to a point where it is too fast for the cards / chips on that bus.

Re:ummm... root cause....

[Chris Burke]

Yeah. I'm thinking power consumption is by far the most likely cause. Of course I don't have any numbers for how much power an actively transmitting wifi chip uses, or the PSP's processor at various frequencies. However given the power budgets of portable devices, I'm guessing the answer is "a lot, relatively" in both cases.

If the PSP processor requires a higher voltage to run at 333MHz, then I'd say this answer is a shoe-in. Power scales linearly with frequency, so going from 222MHz to 333 is a 50% increase in power. But it scales with the square of voltage, so if a higher voltage is needed to run at the higher frequency then that could increase the power requirement of the CPU such that there is no power budget left for the wifi.

Other possibilities? I dunno... a wonky synchronizer between the wifi and cpu clock domains that makes a bad assumption about wifi chip vs cpu/bus speed? I've certainly seen that happen, but I'm really guessing as to whether it applies to the psp or not.

Perspective Please

[JamesRose]

Untill recently, the clock speed was only 222, now they have upgraded it so it can go to the full speed of 333mhz, however, you can't do this while running the wi-fi. People have not found a floor, just a limit to the extra given in the new update, everything was working fine at 222mhz and no one complained about slowness so you should have no problems on the wi-fi, there just wont be the extra snapiness, sony probably only did this to save battery or something.

I just don't see why this is an issue

[G Fab]

I mean yeah, some of y'all don't like Sony and point out everything that happens with this company as though it's a "fuckup" (to take an above commenter's description of this limitation). But it's a fact that the wifi being on didn't slow down any PSPs on any game ever published. The spin here may be tough for some to see through, but to fac tis simple, all PSP games were running at a set speed of 222 mhz. These games could have wifi on or off. I presume that somehow there is a power limitation or something other limitation that means you can't run full speed with wifi. I'm sure this isn't design flaw, unless you think every system that could be faster is designed poorly (and virtually every system could be faster). You have to engineer these things. This announcement is that Sony has now INCREASED the processor speed for non wifi applications. It's a bit of GOOD NEWS. I mean, whoop dee do, who cares, but still, this isn't bad news for anyone. It adds a capability that wasn't there in the past. But here's the spin "WIFI IMPAIRS THE PSP PROCESSOR!!!! NICE DESIGN CHOICE HAHAHA!!!" So strange to twist things that radically. I just don't get the whacky spinning. What did Sony do to deserve this special treatment? I'm sincerely curious. Sony has been pretty cool about Linux on its systems so long as it doesn't lead to pirated games. Sony is always pushing things to add features and be innovative... often valuing cool novel features over functionality. That's how we get new cool stuff. Everybody out there uses something Sony invented. Things as basic as optical discs and modern batteries were developed or improved by Sony. I would think Slashdot would have a lot of people who like Sony because it's got cool stuff. Albeit the nice stuff is too expensive. This seems like more than a economic issue. Some of you, and obviously the editor, have a real axe to grind. Reading through these threads, some dude was modded a troll for a single sentence saying "The Cell processor is a really cool piece of technology!" Anyway, I'd like to hear what the real issue is.

Re:I just don't see why this is an issue

[Babbster]

That's some pretty serious schilling there. Sony hasn't been "cool" about anything homebrew on the PSP (the device under discussion), doing everything they can to disable it with each firmware update.

I could have agreed with you that this isn't a big PSP problem, except maybe in the sense that a developer might make a game without WiFi capability because they decide the increased CPU speed is more important. However, attempting to portray Sony as a poor, hapless, open-source-friendly victim of evil anti-Sony Internet meanies is more than a little ridiculous. For the most part, the folks at Sony earn the wrath of their detractors by making stupid, short-sighted, sometimes downright evil, corporate decisions (I'll skip the laundry list since it's quite well known 'round here).

Oh yeah, and making paragraphs is really easy in HTML. You might want to look into that...

Firmware cat-and-mouse is still on

[tepples]

The PSP's 222mhz processor is still a hell of a lot faster than the 67mhz processor in the DS. Unless you are considering buying a new PSP or new DS to use homebrew. In this case, the PSP is likely to be 0 MHz because it comes with new 3.51 firmware that rejects the Lumines exploit, but the DS with the "Games n' Music" modchip for SLOT-1 ($30 at Wal-Mart stores) is still 67 MHz.