prescott 2.8 @ 100%: 100W too much to be silenced?

misterstick · Post by **misterstick** » Mon Aug 16, 2004 9:06 am

i have a new p4 2.8.

i run distributed.net, so i would like it to run at 100% 24/7.

i tried to run it with a 7000B-AlCu, but intel's monitoring software would report the temperature as 70+ and it would shut down.

replacing the 7000B with intel's supplied heatsink has meant that i can now run it at 100% with the temperature reported constant at about 65.

given that the fans go into overdrive at 50, will better airflow, better thermal paste, bigger, quieter fans, etc really make a 15 degree difference?

should i accept that the only truly silent pc is one that is turned off?

many thanks,
mr s.

POLIST8 · Post by **POLIST8** » Mon Aug 16, 2004 9:13 am

The 7000AlCu doesn't cool as well as Intel's stock Heatsink? Are you sure that it is properly mounted on the CPU?

At full-blast the Zalman should easily cool better than a stock Intel heatsink - were you running the Zalman full speed?

What Power Supply are you running? How many fans are in it?

Do you have an intake Fan?

Wedge · Post by **Wedge** » Mon Aug 16, 2004 1:42 pm

misterstick,

I have to wonder the same questions as POLIST8, because I have a 2.8, which is cooled with a Zalman 7000A-AlCu. I can play Quake for hours (load) without a hiccup. Then I can stop and check the CPU temp (according to Asus's hardware monitoring) and I'll be in the 50's -- usully 52.

I'm thinking that you might have bad CPU-Heatsink contact, restricted intake, or poor exhaust. Or maybe a combination of all three.

misterstick · Post by **misterstick** » Tue Aug 17, 2004 1:05 am

thanks for the responses.

the case is a centurion 1, so the intake blows over the drives. this could be considered restricted. i'll move the drives into the empty external 3.5" bays out of the way.

i fitted an extra outlet fan to the back and on "small hovercraft" this blows air that feels reasonably cool, or rather not unreasonably hot. with the case open the temperatures don't change much either.

i'll certainly try better contact between the sink and the cpu: being new to this game and barely at conscious incompetence level i accept this may take me a while to get right. i was upset that i couldn't use the 7000, it's so beautiful. i'll certainly try again.

the intel seems to cool the cpu better because the rpm is reported as 4500+, whereas the zalman doesn't seem to get beyond 3500.

to get the fans to run in normal mode i would have to cool the box by 15 degrees. my original question was whether this is possible, or whether i have to accept that dissipating 100W of heat takes a lot of air, which is, by definition, noisy.

thanks again,
mr s.

silvervarg · Post by **silvervarg** » Tue Aug 17, 2004 5:24 am

1. Don't move the HDD from the intake path. The HDD is the most sensitive part, and keeping them in the intake path is a very good thing.

2. Cooling 100W of CPU heat is hard, so it will be a bit noisy. (Actually a bit more then 100W since Intel underreports the CPU heat. There is a special thread about this.) The Zalman 7000B should cool better at 3500RPM with 92mm fan than the Intel stock cooler does with 4500RPM. I would defenatly go with the Zalman heatsink.

3. If you are uncertain about the airflow in your case I suggest that you run with the case open as a temporary test. If this works fine, but not with case closed then you should start by checking if you can snip some restrictive fan grills.

POLIST8 · Post by **POLIST8** » Tue Aug 17, 2004 12:46 pm

The Zalman should kick the Shizzle out of that Intel HSF and be more quiet in the process...

I did notice that there is a bit of "play" with the way my 7000Cu sits on my AMD64m CPU, but I've read elsewhere that this is normal.

My temps are excellent, so I haven't thought of changing it.

By the way, did you put the thermal grease that came with the 7000Cu on the Heatsink before mounting?

misterstick · Post by **misterstick** » Tue Aug 17, 2004 1:27 pm

i've had a bit of a play this evening, and here it is.

i replaced the intel sink with the 7000-AlCu and used a shinetsu thermal pad, trying as hard as i could to get the faces as clean as possible and not to move the sink laterally when i put it on (not that easy at first.)

i replaced the qtechnology qt-02350 psu with an antec sl350pec, connecting its fan to a splitter connected to the outtake fan connector.

now it runs at 42/62 open, and 44/65 closed. yay!

the zalman is much quieter than the intel: it doesn't have that high pitched whine.

the case fans are still on hover speed, though, but don't start up until 60 rather than 50 as i had previously thought.

hmm. five degrees.

i'm going to get me some of that arctic silver stuff i've heard so much about, and get my girlfriend's dremel out of the shed to cut me some holes in my case.

wish me luck,
mr s.

shathal · Post by **shathal** » Tue Aug 17, 2004 1:54 pm

A 2.8 Should "no way" be too much to be silenced.

Zalman 7000 (quite happily) quieted down a colleagues 3.0 GHz P4 (Prescott), so you should be good. Or, if you want go "deluxe" and consider upgrading to a 3.4 GHz or so sometime, consider the XP-120, which DEFIANTELY pacifies Prescotts quite darn well

.

Wedge · Post by **Wedge** » Tue Aug 17, 2004 3:20 pm

Another satisfied customer in mr s.

Like POLIST8 said, the 7000 is the shizzle. I don't think I've seen many posters expressing disatisfaction with it. I'm a repeat buyer -- started with the copper version for my first build; went with the AlCu on the second. Although the copper sits on a 1.7GHz, while the AlCu sits atop a 2.8C, I am getting similar temps for each processor and the fan mate is at its lowest setting - not *silent* but extremely quiet.

Bluefront · Post by **Bluefront** » Tue Aug 17, 2004 3:32 pm

My Prescott 2.8 runs happily, and relatively cool (44/53C), with an Alpha 8942 and a generic 80mm fan (suck mode).....max rpms about 2500. With the Alpha blowing up, the heat off the CPU is immediately exhausted by the rear case fan.

I don't like that Zalman HSF because of it's size. Way too big to fit many boards....