I read the wiki on overclocking my router and the appropriate values to use, but it does not say anything about having been tested on a WRT54GS. I would kind of like to avoid bricking it if I can.... so will the values listed in the table work?

Also, anyone have any idea how/if this affects wireless speeds?

The values on the wiki have been tested; 300 works but I probably wouldn't go above 264.

EDIT: retracting that statement; 240 seems stable but please understand that recovering from a bad setting requires a jtag cable.

(Last edited by mbm on 17 Jun 2005, 23:03)

I have overclocked two WRT54GS boxes, one would run at 300, the other would not go higher than 240.  Use extreme caution unless you are willing to build a jtag cable interface.  There is really no way to recover an overclocked brick without it.

It does affect wireless speeds from my experience.  I was only getting 1.8MegB/s running at 200mhz, and after overclocking to 300Mhz, I get 2.5MegB/s.

Yes and no, normally this requires a JTAG to reset nvram; inh and I have figured out how to get the power-while-holding-reset to actually recover from this, requires some changes to the cfe defaults. This may be a catch-22 since I wouldn't recommend updating CFE without a JTAG.

Are there any reports that overclocking actually damaged the hardware?

It does not look like my router is doing too well after overclocking it. I put in the following commands...

root@192.168.1.1's password: 


BusyBox v1.00 (2005.05.25-20:30+0000) Built-in shell (ash)
Enter 'help' for a list of built-in commands.

  _______                     ________        __
 |       |.-----.-----.-----.|  |  |  |.----.|  |_
 |   -   ||  _  |  -__|     ||  |  |  ||   _||   _|
 |_______||   __|_____|__|__||________||__|  |____|
          |__| W I R E L E S S   F R E E D O M
          
root@OpenWrt:~# nvram set clkfreq=264,132
root@OpenWrt:~# nvram commit
root@OpenWrt:~# reboot
root@OpenWrt:~# Connection to 192.168.1.1 closed by remote host.
Connection to 192.168.1.1 closed.

...and it did not come back up. Any ideas where things went wrong, or what is going on?

The commands are right, perhaps as netprince said some routers just can't handle it; device can be recovered with a JTAG cable to erase nvram.

Ouch.... can I short the pins instead of using a JTAG cable and get the same effect? I would rather not attempt building one.

(Last edited by m51dps on 17 Jun 2005, 22:55)

Possibly, but you have to understand that the shorting the pins shown on the wiki only makes it appear as if the firmware is corrupt, a different set of pins would be needed to hide the nvram data from the bootloader. Poking at random pins to figure that out is a very good way to do some serious damage; your safest option is using a jtag cable.

It looks like I lack a computer with a parallel port, and it would be a mess building a JTAG cable.... so I wonder how much a new router costs these days and how long it will survive my own stupidity.

ouch. you DID remember to flash my modified CFE image first right? so all you have to do is reboot while holding reset to use default nvram values and be fine?

No? well then, looks like you get to jtag it, or if you want you can send it to me, i'll fix it, and send it back. your call. email inh[at]burntmail[dot]com

I have tried shorting the pins as a method of recovery, but it failed.  I did end up having to build the jtag cable.  I *should* have installed the custom CFE before overclocking.

I've overclocked to 216 on probably a dozen WRT54G v2.0 and v2.2 without any problems - until now. Just tried it on another one but it appears to have bricked it.

I hadn't tried the CFE modifications mentioned on here which would allow me to reset NV as I expected this hack to work without any problems. I was hoping to use this hack on all boxes but even if there's a 1 in a 100 chance it could screw somebodys box up I can't :-(

Is this a one off or have other people had the brick fairy come and visit them for overclocking to 216?

[famous last words]I do not want to go through all of the trouble of recompiling a kernel and putting together a new CFE file.... I mean, all I am doing is overclocking it, what's the worst that could happen?[/famous last words]

I really had to learn my lesson the hard way....

I've tried to overclock my WRT54G v2.0 (OpenWRT experimental, jffs2), but neither "nvram set clkfreq=216" nor "nvram set clkfreq=216,108" worked. After "nvram commit" and "reboot", the router constantly reboots in a loop. On a serial console, the boot messages say that the cpu runs at 252 MHz.

Setting clkfreq to 228 or 240 works.

Tried overclocking at 216 MHz on two v2.0 boxes.
One works fine, the other got bricked and started resetting itself every 20 s. or so.

Managed to recover it by powering up and bringing it in failsafe mode (200 MHz).
Then connected via telnet, and gave firstboot, mtd erase nvram, and reboot.

In any case the 216 MHz setting is not failsafe on v 2.0 units!

doddel

I forgot to say that i have Rev XH of the WRT54G v2.0 with 32 MB enabled . Could this affect the possible cpu frequencies ?

I overclocked a WRT54G v2.0 to clkfreq=216 with no problems.

I tried to overclock a WRT54GS v1.0 (same hardware revision as a WRT54G v2.0), to clkfreq=216 and had major woes - it's rebooting in a loop.  Looks like it's JTAG time for me.

Will hairydairymaid's JTAG flashing program work on a WRT54GS?  If so, is there a fresh NVRAM image out there for a WRT54GS v1.0 that I can use to restore my NVRAM?

Dan

If you have a serial connection to your WRT, you can try another recovery method.  Enter CFE by rebooting the router while hitting "Ctrl C" continously until you get the "CFE>"  prompt. There you can set clkfreq back to 200 and reboot your router. With this method i could recover my wrt54g.

Dan,

You have to have version 3 of hairydairymaid's JTAG flashing program to support the 8meg flash chip I believe...

I have recovered 2 wrt54gs with it.

Hi,

just to post my experiences: on my wrt54gs v1.1 overclocking to 228 by setting clkfreq to 228 bricked my device. 216 MHz worked, but didin't fix the reboot-on-high-load-problem. I read in the forums that people got the same device with the same fw-version running without problems on 228 MHz, so my advice is just to be careful.

Just my 2 cent.

Hi All,

An amazing recovery...

I overclocked the WRT54G v2 without updating the PMON firmware using the clkfreq=216, commited and rebooted. From that moment on it was restarting continously: Bricked.
I build a JTAG cable but because I'm using virtual PC and the parport modules kept in the way I tried another approch:
I put the brick into the freezer for a few minutes to let it cool down. When applying power it started up and was able to unset the clkfreq value by executing mtd erase nvram. It looks that a cold WRT supports overclocking better.

Just lucky or maybe a logical explanation? Hope this works also for your bricked routers...

Has anyone tried attaching some type of a heatsink to the broadcom chip to increase overclocking potential?  Haven't seen anyone do this.

Personally, I have never had my processor get too hot to touch, so I figured it was OK.  I have seen pictures with heatsinks attatched to the processor and memory, check into the documentation under customizing.