What heatsink for E8400?

[Solarium]

Is there any cheap heatsink that's significantly better than the one that comes with the CPU, anything for a good temp (40 C) at 3.6ghz O/C'ed.

Thanks

Btw, can someone please also explain why would you only use a PC6400 (800mhz) DDR2 ram at 3.6? Is it possible to use say 1066mhz at 3.6ghz CPU? I'm pretty nub to the DDR2 scene so I'm clueless.

 

[DarkRogue]

I personally use the Scythe Ninja Plus and am very happy with it. I don't have spectacular TIM since I had plenty of Ceramique lying around, so if you use something better it will be about 5-10 degrees (best case) cooler. I've OC'd it to 3.6GHz and it's idling at just around 40C.

I know there's a Xigmatek that's been thrown around recently, I don't know what model that is though, someone else can step in to help you out there. I chose the Ninja because of its ability to cool passively if needed, but otherwise an undervolted fan cools well and is extremely quiet.

It's normally suggested to use PC6400 DDR2 because its speed is, as you said, 800MHz. DDR = Double data rate so half of 800 is 400MHz. CPUs are "quad pumped" meaning it takes the base FSB speed and multiplies it by 4. The E8400 natively comes at 1333MHz "quad pumped" or an FSB of 333MHz. To achieve the 3.6GHz overclock, it's usually upping the FSB to 400 while maintaining the core multiplier at 9x. 9x400 = 3600 or 3.6GHz. The base speed of both the CPU and RAM are now 400MHz, and this means they can run synchronously with each other, which is usually the best way to run it.

Hope that helps.

 

[chinaman1472]

Arctic Freezer 7 Pro is on sale at eWiz.
Xigmatek HDT-S1283 is a banging deal at $37.

 

[Blain]

Originally posted by: Solarium
Is there any cheap heatsink that's significantly better than the one that comes with the CPU,

Would you also like for it to wax your car and bake you bread?

 

[Roguestar]

Arctic Freezer Pro 7.

Don't expect major differences when shelling out minor $$$.

 

[s44]

Define "cheap".

 

[DSF]

It isn't that you need to have DDR2-800 to hit 3.6GHz as opposed to DDR2-1066. It's that running an E8400 over 3.6GHz requires RAM faster than DDR2-800. (Or it reqires overclocking your RAM, if you have sticks capable of that.)

Edit: Also, I think you should define "cheap". People are throwing around heatsinks in here that are in the neighborhood of $30, which I wouldn't really consider cheap. As someone said though, if you're looking to spend less than $30 don't expect a world beater.

 

[Solarium]

Originally posted by: DSF
It isn't that you need to have DDR2-800 to hit 3.6GHz as opposed to DDR2-1066. It's that running an E8400 over 3.6GHz requires RAM faster than DDR2-800. (Or it reqires overclocking your RAM, if you have sticks capable of that.)

Edit: Also, I think you should define "cheap". People are throwing around heatsinks in here that are in the neighborhood of $30, which I wouldn't really consider cheap. As someone said though, if you're looking to spend less than $30 don't expect a world beater.

Cheap is under $50, but I'm looking for the cheapest possible heatsink that can cool the CPU to a safe and stable temperature O/C'ed to 3.6ghz.

How does the Scythe Ninja Mini stack with the Xigmatek and AC Freezer 7 Pro? I had an AC Freezer pro 64 for my old Athlon 64 3400+, it ran pretty quiet, are these heatsinks along the same line of quietness?

As for the overclocking, my take is that in order to use 1066 ram you need to up the FSB to 533, along with the CPU itself, and since it will hit 4.8ghz with a 9x multiplier, you would need to change the multiplier for it to properly work at 3.6ghz. Do the E8400's come unlocked? Also, what is the "1333mhz" mean on the E8400, is it its base speed, so you would be changing that to 1600mhz as soon as you change the mobo's FSB to 400?

Thanks for the help, it really helped me understand these things a bit better

 

[DarkRogue]

E8400's are not multiplier unlocked, they go from 6-9x with 0.5x increments. 1333MHz is its rated FSB, but it's "quad pumped" so divide that by 4 to get the base FSB value, which is 333MHz. Upping the FSB to 400 will mean it gets quad pumped to 1600MHz.

Most of these heatsinks are under the $50 price point, but if cheaper is better, I've heard good things about the Arctic Cooling Freezer 7. It's cheap and gets the job done.

 

[Roguestar]

If you stick in 1066MHz RAM you don't have to change anything, the RAM will downclock to whatever the FSB is running at unless you mess with it. You don't change the CPU's FSB multiplier. And infact you can't.

The E8400 CPUs do not come unlocked, only the "Extreme" branded CPUs with an X in the model have unlocked multipliers.


BASICALLY:

Core 2 Duo CPUs run at either "1066" or "1333" FSB.
This is "quad-pumped" as it send four bits per cycle and the number quoted is an "effective FSB speed" and not the actual physical speed.
The actual physical speeds are 1066/4 and 1333/4 or 266 and 333MHz respectively.
In order to overclock these CPUs, one must raise the FSB. Raising the FSB from 266 to, for example, 400, raises the "effective FSB speed" from 1066 to 1600.

DDR2 RAM's quoted speeds are in fact twice the speed they are running at. So a DDR2-800 stick will run at a maximum of 400MHz without overclocking.
When you put a DDR2-800 stick in a 1066 or 1333 (266 or 333 physical speed) motherboard/CPU combo, it will downclock itself to run at 266 or 333, whichever the processor is running at.
The memory will generally try and run at the same speed as the FSB, so if your memory is DDR2-800 and your CPU FSB is 1333MHz then it is slowing itself down from 800/2 to 1333/4, from 400 to 333.
As you increase the speed of the FSB in the CPU, the memory will attempt to scale upwards with it and maintain a constant ratio with the CPU.
Thus, if you overclock a 3GHz 1333FSB (333 physical) CPU with a x9 multiplier (333x9=3GHz) to 3.6GHz (3.6/9 = 400MHz), you will be adjusting the FSB from 333 to 400MHz.
At this point, the memory will now be running at effectively 800MHz; the level at which DDR2-800 is rated for.
If you wish to push past this FSB point, you will be making the memory run faster than that which it is rated and are 'overclocking' your RAM.
This means that anything past 400MHz FSB is not guaranteed for by DDR2-800, and is why some people use DDR2-1066 (which will guarantee them headroom up until an FSB of 1066/2 = 533).

 

[Solarium]

Originally posted by: Roguestar
If you stick in 1066MHz RAM you don't have to change anything, the RAM will downclock to whatever the FSB is running at unless you mess with it. You don't change the CPU's FSB multiplier. And infact you can't.

The E8400 CPUs do not come unlocked, only the "Extreme" branded CPUs with an X in the model have unlocked multipliers.


BASICALLY:

Core 2 Duo CPUs run at either "1066" or "1333" FSB.
This is "quad-pumped" as it send four bits per cycle and the number quoted is an "effective FSB speed" and not the actual physical speed.
The actual physical speeds are 1066/4 and 1333/4 or 266 and 333MHz respectively.
In order to overclock these CPUs, one must raise the FSB. Raising the FSB from 266 to, for example, 400, raises the "effective FSB speed" from 1066 to 1600.

DDR2 RAM's quoted speeds are in fact twice the speed they are running at. So a DDR2-800 stick will run at a maximum of 400MHz without overclocking.
When you put a DDR2-800 stick in a 1066 or 1333 (266 or 333 physical speed) motherboard/CPU combo, it will downclock itself to run at 266 or 333, whichever the processor is running at.
The memory will generally try and run at the same speed as the FSB, so if your memory is DDR2-800 and your CPU FSB is 1333MHz then it is slowing itself down from 800/2 to 1333/4, from 400 to 333.
As you increase the speed of the FSB in the CPU, the memory will attempt to scale upwards with it and maintain a constant ratio with the CPU.
Thus, if you overclock a 3GHz 1333FSB (333 physical) CPU with a x9 multiplier (333x9=3GHz) to 3.6GHz (3.6/9 = 400MHz), you will be adjusting the FSB from 333 to 400MHz.
At this point, the memory will now be running at effectively 800MHz; the level at which DDR2-800 is rated for.
If you wish to push past this FSB point, you will be making the memory run faster than that which it is rated and are 'overclocking' your RAM.
This means that anything past 400MHz FSB is not guaranteed for by DDR2-800, and is why some people use DDR2-1066 (which will guarantee them headroom up until an FSB of 1066/2 = 533).

Amazing explanation, I get everything clearly now. Thank you

 

[Roguestar]

No worries, happy to help . For all the time it took I might actually format it better and save it to a text file for future needs :thumbsup:.