So far... I have achieved it for low load usage. All thanks the the northbridge register hack posted by..... I cannot locate the thread at the moment.
Chip is AXP 2600+ Barton at stock clock speed(167FSB*11.5) and stock voltage(varies between 1.63-1.65). Motherboard is A7V600-X
Heatsink is a fairly rough based and dusty Spire WhisperRock IV. It has ran passive for the last 4 hours without crashing. Idled at around(with some chatting on MSN messenger)45C-48C, currently playing music and browsing the web on Firefox at temperatures ranging between 57C-59C. No thermostat in room, but I would guess around 15C-18C in room.
Setup of the computer is one 5V 80mm intake fan at the front, one 5V 80mm intake on side panel, one 5V 80mm blowhole on top, Seasonic Super Tornado 300 sucking at 820-830rpm. Full 12V 80mm blowing on stock Sapphire 9600XT heatsink with fan removed. Oh yeah, CoolerMaster fan decoupled on heatsink, not spinning. Will have to turn fan on for any intensive activities.
Hoping for even better efficiency when I smooth out the base of the heatsink after my exams.
Passive cooling on stock AXP 2600+ Barton
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