votes please!
i'm buying the 125w version of Phenom II X4 965 BE.
I want to use my old cooler: Scythe Ninja + rev B with NO fan (as i currently do with my opteron 175)
Do people think this will work, with ninja close to rear case exit (nexus 120) fan?
Will Scythe Ninja+ RevB passively cool Phenom IIx4 965 125w?
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I'd say no.
I have a C2D E8400, which should use something like 35 watts under load. It is cooled by a Thermalright HR-01 Plus. Without the complementary Air Duct, when it is cooled by the rear exhaust fan (Nexus @5V) much like the Ninja would be in your case, the CPU temp gets pretty high, 60-something degrees, though that's still tolerable.
Now a monster 4-core CPU like that X4 of yours is very unlikely to be sufficiently cooled (pseudo-)passively.
I have a C2D E8400, which should use something like 35 watts under load. It is cooled by a Thermalright HR-01 Plus. Without the complementary Air Duct, when it is cooled by the rear exhaust fan (Nexus @5V) much like the Ninja would be in your case, the CPU temp gets pretty high, 60-something degrees, though that's still tolerable.
Now a monster 4-core CPU like that X4 of yours is very unlikely to be sufficiently cooled (pseudo-)passively.
oh dear. but i'm willing to increase my rear Nexus to eg. 7-9 V, or eg. 20% off max speed.
i just want to know if I also need to buy a new cooler if i want to do it passively.
BTW maybe i'm being silly, but my Opteron 175 (currently passively Ninja-cooled - easily) has a TDP of 110W, whereas my proposed Phenom 965 has a TDP of 125W - so i'd assumed not too much difference in cooling requrements - is that a false assumption?
CA_Steve - good question. I think no more than 55 degrees under load - but i'll check tonight and post here.
i just want to know if I also need to buy a new cooler if i want to do it passively.
BTW maybe i'm being silly, but my Opteron 175 (currently passively Ninja-cooled - easily) has a TDP of 110W, whereas my proposed Phenom 965 has a TDP of 125W - so i'd assumed not too much difference in cooling requrements - is that a false assumption?
CA_Steve - good question. I think no more than 55 degrees under load - but i'll check tonight and post here.
Here's a very crude answer that ignores a lot of variables. Assuming 20C room temp...
Your current system has a core temp rise of 55-20C = 35C. The Opteron has a TDP of 110W. So, the thermal resistance is 35C/110W = 0.318C/W
The thermal rise with the 125W CPU would be = 125W*0.318C/W = 40C
So, you'd see a core load temp of 60C.
There are so many other factors involved that this is a wild assed guess...but assume the minimum increase versus your current solution is 5C higher.
Honestly, I'd buy a low rpm silent fan just to be on the safe side.
Your current system has a core temp rise of 55-20C = 35C. The Opteron has a TDP of 110W. So, the thermal resistance is 35C/110W = 0.318C/W
The thermal rise with the 125W CPU would be = 125W*0.318C/W = 40C
So, you'd see a core load temp of 60C.
There are so many other factors involved that this is a wild assed guess...but assume the minimum increase versus your current solution is 5C higher.
Honestly, I'd buy a low rpm silent fan just to be on the safe side.
What really maters is the actual power draw of the chip and not the TDP value which is an arbitrary number. The phenom`s power consumption is probably more than 15 watts higher than the opteron`s which is why people are suggesting passive cooling is a no go.
Check x-bit`s power consumption graphs if you want to get a feel of how the phenom compares to other modern cpu`s.
You could increase the speed of the rear exhaust but it will probably be more efficient, and thus quieter, to just add a fan on the heatsink and keep both at low speeds.
Check x-bit`s power consumption graphs if you want to get a feel of how the phenom compares to other modern cpu`s.
You could increase the speed of the rear exhaust but it will probably be more efficient, and thus quieter, to just add a fan on the heatsink and keep both at low speeds.
ok, so i ran cpuburn (i found i had to run 2 copies to get both cores maxed out) and after a few minutes my 'core' (assume nForce 4 chip) was at 70 deg, and CPU was at 62 deg - this was with both front & rear case fans at full speed!
so i think y'all are right. having said which, i don't see myself ever stressing the cpu that much - it's a sort of artificial test.
I think it will at least be feasible at idle, so I'll do the build without a fan, do some testing and post back here.
thanks for the input.
so i think y'all are right. having said which, i don't see myself ever stressing the cpu that much - it's a sort of artificial test.
I think it will at least be feasible at idle, so I'll do the build without a fan, do some testing and post back here.
thanks for the input.