Posted: Sat Apr 10, 2010 18:38 Post subject: Three cooling mods...
What got me started on this was the Asus RT-N16; which has been the bane of my experience in terms of messing about with upgrading my home network. Below are a few pics showing my efforts to get this thing running cooler. I used a thermocouple and stuck it to the heatsink of the warmest part in the box. With passive cooling it would hover at ~135F under about half load. With the active cooling mod it typically is less than 95F. I was neglectful and never measured the temperature with the stock heat sink. I can safely assume it was higher than 135F since you can see the mass of the new heat sink v/s the mass of the stock heat sink is significant. The stock heat sink is the upper left square in the picture.
The fan has a little bit of hidden hardware to it. I added a couple of 1N4004 diodes to make sure there wasn't any flyback due to the fan. I don't think it'll be an issue, but why take chances? I also added about 75 Ohms of resistance to keep the current draw of the fan down (less than 100mA). This impacts the speed and airflow of the fan. You can see from the data above that I'm still dropping the temperature of the system dramatically at a lowered airflow rate than the fan is capable of.
[ Is gonna be a bandwidth killer for a little bit, and I did bother to shrink these down a bit too. ]
My next victim -- uh, mod was my old Linksys WRT54GS V6.
I bought the Asus router to replace this unit, and I was deathly afraid of bricking it -- it was harrowing, but I didn't. When the N16 gave me fits, I went back to this unit. I knew it warmed up a bit over the years I've had it in service, so when I got a bit of inspiration, and more thermal epoxy, I glued an aluminum spacer to the top of the Broadcom chip. Again, the thermocouple measured this guy at ~140F with the spacer on it. I then took advantage of the fact that the spacer is threaded and just screwed on more aluminum. I also did thermal pads on the radio ICs here too. This guy is just my rock-solid workhorse now. As a bonus, I upped the transmit power from 71mW to 75mW and it has been stable for about 50+ days. Can't complain about that.
As a side note, you borderline need plastic explosives to pull this case apart. It all snaps together and I ripped the shell up pretty bad trying to figure out how to open it.
[ Knows this one was pretty ghetto-rigged, but I got results, and this pleases me. ]
Whew, last one. This is a Netgear WNR834B v2 that I just picked up and got DD-WRT on. Since I had clearance problems and lacked any nice heat sink material, I repeated what I did on the Linksys router. The unit runs pretty cool now and so far stability is good. It's funny, the inverted heat sinks look like square mushrooms in a way.
Questions? suggestions? Bear in mind, a lot of this stuff was scrounged up from broken bits and extras, the only thing I spent any real money on were the routers and the thermal epoxy. :D
What is better cpu water cooling or regular fan with heat sink ?There's a lot of water cooling products around but I'm not sure if water cooling is better or can be a problem when the system leaks.