I noticed we didn't have any articles with reference to overclocking this legacy router, so I decided to share this tip (credit goes to the modding/dd-wrt/tomato/openWrt etc. community).
First note however: Do this at your own risk! This may damage your router.
The CPU clock frequency is by default set at 240MHz, it is my opinion that generally you are given a good headroom of 5-10% range without additional cooling. For my situation, this would be 250MHz to 260MHz.
To enable overclocking, you'll need to flash your router to variant of DD-WRT. If you have not flashed it to DD-WRT, you will want to do the initial flash which ends in the .chk extension. Once your router reboots into DD-WRT, then you'll need to choose a flavor of DD-WRT depending on your needs or preference. I chose to go with nokaid-generic version because its a tad lighter on the RAM than the full generic.
Once you've got DD-WRT on the router, you will need to telnet or SSH into console.
To overclock, follow these steps:
root@router:~# nvram set clkfreq=(value)
root@router:~# nvram commit
root@router:~# reboot
(value) ~ 240, 250, 260, etc.
Once you have finished, your DD-WRT router status page should reflect the overclocked value.
Don't perform nvram commit until you have thoroughly tested out your router's reaction, otherwise if you commit that to nvram and your router does not play happily with that frequency, your router end up boot-looping.
If you look at http://www.dd-wrt.com/wiki/index.php/Supported_Devices, I did not find any devices that come pre-configured with speeds above 240MHz for this chipset, keep this in mind when you decide what speeds to run it at. Personally, I would not have overclocked at all if not having popped in small heatsink I had laying around for an old i486 processor. It was thin enough and also fit the dimensions properly to be mounted and glued in.
-MCHIU
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