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40mm fan on greenie below Alpha, do I let it suck or blow?

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Feb 12, 2001
the Netherlands
Hey I've been upto 135Mhz FSB with my Celeron this week, but for some reason over a few days it kept needing more and more upping of voltages to stay stable. I have good case cooling and a little HSF on my videoboard, but nothing on the northbridge-greenie. So I wanna get a (old 486?) 40mm fan to put on the greenie, and see if this stabilizes things. But my Alpha is hanging right above it sucking air out. How would I mount the greenie-fan? also sucking out (thus blowing into the Aplha)? and will this affect my CPU temps? (See the pic)
i kind of have this same problem. my alpha 6035 with a delta 38 on it sticks out even farther than your pep 66 on my bx6 2. little greeny never gets warm to the touch and my system temps arent too high so i dont worry about it.
I also had the same situation with a slocket and a C2-566. The HSF moved enough air over the greene to keep it cool. One thing I did is remove the greene and lap it. Many of them are in sad shape with only the edges touching the northbridge, mine was concave. Also it had no grease on it. Between the lapping, adding grease, and the HSF moving air over it I never had any problems and it ran cool. The 566 ran at 1020mhz with a 120fsb.
I didn't lap it, but I did add thermal paste. It still feels pretty warm, even at my current 'low' FSB of 112Mhz.
I have a Alpha P3125 hanging over my northbridge and I stuck a 40mm fan on the greenie sucking air up. I applied AS2 on the greenie too, required quite a bit as the chip was concave. Digital Doc 5 shows only no temperature difference before and after . I am tempted to screw a 50mm fan to the bottom on the alpha, hopefully this push/pull configuration will cool the cpu better and helps cool the greenie too.
I have though about doing the same thing, since I'm in a similar situation, with my BE6-2, P3-700 flippy and an Alpha PEP66T.

I applied a thin layer of artic silver on the greenie. Didn't lap it tho, as it seemed to cover (almost) all the surface area. I also considered adding a small fan, but came to the conclusion that the air from the alpha should keep the greenie somewhat cold.
Yesterday I got a "justcooler" chipset cooling-kit with a ADDA 40mm fan and a few tiny heatsinks with thermal fragtape. I lapped my greenie (it turned out to be very concave), mounted the ADDA fan on top of it, and put the whole thing back in with a new coat of thermal grease. The greenie fan is sucking air out, thus blowing right into the back of my Alpha which is also sucking air out. (see the pic below) So far no noticable rise in CPU temps :) I stuck the other small heatsinks to the main chips on my SBLive! and 3com NIC. I'm thinking about writing a small article about all my case cooling mods so far.