I´m Doing A Voltagemod.


lippy

Still Fresh
Joined
Mar 26, 2006
Messages
91
Taking bets to what mhz he can get it to!!!...I'm putting my money on 342!
 

Epicenter

Very Active Member
Joined
Oct 9, 2005
Messages
2,068
Age
36
Location
USA
Website
www.epicgaming.us or http
Don't get too over-zealous ... if that's not a 266 MHz part marked down it's unlikely he'd get past 300 MHz. I do have high hopes for my unit that reaches 317 MHz in short bursts though, of achieving stability at 320 MHz when I have time to apply a voltage hack to the 920T. In due time.. :p

At any rate I'm having fun just making sure all my code is fast enough to run at 200 MHz! I can see the neat benefits of overclocking later :)
 

OMG

Still Fresh
Joined
May 31, 2006
Messages
95
Games are 4 times the intentional speed! WOOOOOOOOO F U Vsync!
 

nubie

Recovering Jerk-A-Holic
Joined
Oct 19, 2005
Messages
2,749
Location
USA California
Website
Visit site
Fishbong posted on May 31 2006 at 03:38 PM said:
Ok, now i know what to do. Just one day patience until i get the required parts...
I knew you could do it, waiting patiently. (Nothing else to do but work :))
 
Last edited by a moderator:

Fishbong

man of poor reputation
Joined
Apr 23, 2004
Messages
2,730
Age
35
Location
Hildesheim, Germany.
Website
Visit site
lippy posted on May 31 2006 at 11:24 PM said:
Taking bets to what mhz he can get it to!!!...I'm putting my money on 342!
My GP2X can reach 290 - 285 MHz right now. (depends on the software) I´m happy if i can clock to 310 MHz after i modded it. It´s also possible that nothing will change

Epicenter posted on May 31 2006 at 11:53 PM said:
Don't get too over-zealous ... if that's not a 266 MHz part marked down it's unlikely he'd get past 300 MHz. I do have high hopes for my unit that reaches 317 MHz in short bursts though, of achieving stability at 320 MHz when I have time to apply a voltage hack to the 920T. In due time.. :p

At any rate I'm having fun just making sure all my code is fast enough to run at 200 MHz! I can see the neat benefits of overclocking later :)
I haven´t figured out how to increase the voltage for one core separately. It would probably not work anyway, since the cores have to communicate with the same voltage, so raising the voltage for one core would most probably result in huge problems.

Another annoying thing is that the reference voltage for the A/D converter is also increased, that means that maybe the battery warning light will be on all the time, because the processor thinks the Battery voltage is too low when in fact the reference voltage is too high.
 
Last edited by a moderator:

OmarNawaz

Member
Joined
May 15, 2004
Messages
663
BradN posted on May 27 2006 at 06:48 AM said:
Well, that answers what the max safe voltage to use as DC input is: 5V. (Although, the application note says the acceptable range is 1.8 - 3V, not sure if they're just writing typical battery voltages, or if it really won't work properly above 3V in that setup)

wait so your teling me it safe to run gp2x off a 5v battery?
 
Last edited by a moderator:

Fishbong

man of poor reputation
Joined
Apr 23, 2004
Messages
2,730
Age
35
Location
Hildesheim, Germany.
Website
Visit site
The converter chip can take any voltage from 5V - 2,2V and steps it up or down to 3,3V. The output voltage can be adjusted by changing the resistance of the resistors R211 and R212.
 

BradN

Member
Joined
Jun 22, 2003
Messages
577
The specifications say it can run with up to 5V input, but the application note on the page I googled that shows how to get 3.3V from 2 battery input lists the input range as 1.8 to 3V, so I don't know if they were just writing typical battery ranges, or if components really should be changed to go above 3V input. It probably wouldn't damage it, but might lead to noisier output if some values aren't altered. I don't know enough about it to be sure.
 

OmarNawaz

Member
Joined
May 15, 2004
Messages
663
mhhhh it would make my life so much easier if it does take 5v

should i risk it though mmhhh
 

OmarNawaz

Member
Joined
May 15, 2004
Messages
663
okey doke will do

I have my gp2x running of a 7.2v 1500mah battery I use a DC/DC converter to drop the voltage to 3.3v I then have a seperate 7805 to drop the voltage to 5v for the USB port

I if it runs off 5V i can just use that because the DC/DC converter will take up too much space

face_Sony_NP-FM50.jpg


this is the battery im using its from a sony camcorder

by my measurements it should fit in the cavity where AA's go if i remove the plastic AA battery supports

it will protude by a couple of mms though as there one lil component on the gp2x PCB that doesnt let it sit flush with the board

I havent got a chance to do a battery test but since I recieved it and charged it last week it hasnt run out yet note that I havent been playing with it extensively I watched lost season two finale on it and i know my lil bro been playing music through it.

Sooo i thinks it should last for ageeeesss Im looking to get a TI converter as the 7805 is very ineffiecient.
 

Fishbong

man of poor reputation
Joined
Apr 23, 2004
Messages
2,730
Age
35
Location
Hildesheim, Germany.
Website
Visit site
Seems like i was too optimistic. While i can increase the voltage, it doesn´t seem to have any impact on overclocking. There must be some limitation protecting the cpu, like some diodes...

A strange thing i noticed is that the screen backlight of the GP2X got darker when i cranked up the voltage... not much, but noticeable.

I´ll keep trying. The GP2X power supply is far more complicated than the GP32 one, so it may take time...
 

nubie

Recovering Jerk-A-Holic
Joined
Oct 19, 2005
Messages
2,749
Location
USA California
Website
Visit site
EDIT: I found squidges post but it says nothing about 5v :(

should i just try?

If using the battery contacts then I would.

Was he using the battery contacts? I have the datasheet on our regulator, it clearly states 5v as an acceptable input.

Will a 7805 take the current you are putting through it, more than 1 AMP, closer to 1.5 Amps?

I would love to see the heatsink :).
 
Last edited by a moderator:

OmarNawaz

Member
Joined
May 15, 2004
Messages
663
woot it worked

running fine it seems

about the heat sink im using a chipset heatsink of a old mobo im incorporating into the case heat is minimal not a case melting levels

gonna pick up some ram heatsinks tomorow saves me hacking away at the one i got

Im wiring up the USB port tomorow woot
 

Radek

Certified Guru
Joined
Oct 13, 2005
Messages
871
Seems like i was too optimistic. While i can increase the voltage, it doesn´t seem to have any impact on overclocking. There must be some limitation protecting the cpu, like some diodes...

Or a critical signal propagation inside the chip is too long and it's preventing it running any faster. Overvolting will not help if it's such case.

There we have also other components like a memory. It will also limit possible clockrate as it's working synchronously with MMSP2 chipset.

A strange thing i noticed is that the screen backlight of the GP2X got darker when i cranked up the voltage... not much, but noticeable.

It's looking like the powerregulator starts to be insufficient in coping with higher power demand?

I´ll keep trying. The GP2X power supply is far more complicated than the GP32 one, so it may take time...

Your research is very interesting.
 
Last edited by a moderator:

jmetal88

Erm.... Woohoo!
Joined
Mar 31, 2004
Messages
1,838
Age
32
Location
Pittsburg, KS
Website
mikesweb.exofire.net
nubie posted on May 26 2006 at 11:55 PM said:
Does anyone remember the console that used 3 AA, was it the Lynx 2?

No, the Lynx II used 6 AAs, just like the Lynx I, GameGear, and Nomad.

I don't know of any that use 3.
 
Last edited by a moderator:
Top