Asus P4P800 SE motherboard, Intel 865PE chipset, 512MB of Kingston RAM and an nVidia FX5200 128MB video card.

The Prescott is one HOT chip. I have to underclock it 30% each time I boot (from 2.4 to 1.68GHz) using the Asus Overclock utility that came with the mobo, just to keep it to around 55C in an air-conditioned room with the side of the case off.

Normal CPU usage is 2 - 5%, but as soon as I start anything that uses more of the CPU, the temperature starts to rocket. Flash games, playing or burning CDs, AdAware scans etc. all send the temperature to 70C at which time I just stop whatever it is I'm doing and let it cool down.

I don't want to install some heavy-duty heatsink/fan combination because I think it will be a waste of effort. I think Intel screwed up royally with the architecture of the Prescott - I think it's their first to use 90nm technology.

I want to replace it. Is this possible, and does anyone have any suggestions as to what would work well? I don't need a super-fast replacement, just one that stays cool.

Think you'll be forced to "downgrade" to a Northwood core

If it was my machine, i'll buy a BIG cooler and open a big air inlet hole on the tower's left cover

I opened a 80mm diameter hole on mine, this drop down the temperatures on 6 degrees, before adding another exhaust fan to the rear. Now, my system runs with 11~12 oC lower than when I built it.

Just buy an Athlon64 and be done with Intel Ed

The meltdown temperature for an AMD chip has traditionally been approx. 90C. I know that Intel chips have safety shutdowns, so the possibility of melting your chip is remote. If your unit runs okay at 70C and holds that temperature, don't worry about it. As long as it is running normally, if it runs a little hot, so what? AMD is notorious for big swings in chip temperatures depending on which one you use. I have built many units using AMD chips, and each one runs a different temperature! My present Barton 2700 runs comfortably at 62C, and has been doing quite well for 1.5 years, thank you. I just built a unit for someone using the Barton 3000 @ 400FSB (one fast puppy!) and it whizzes along at 38C, same box and fan setup. Go figure.

Ed, from your description I'm assuming that you have a custom built computer with an inadequate or poorly installed cooler unit. The Prescott chip is very hot (temparature wise ) and needs a good heat exchanger. The first level of heat exchange is dependent on the thermal paste that hides the defects on the chip & heatsink surfaces & I'd recommend a good grade of paste here (like Arctic Silver) instead of the the thermal pad that normally comes with many coolers - if you did have the cooler installed with the pad, that could be your problem. The second level of heat exchange is the heatsink - for something like your chip, you need a substance that has high thermal conductivity and the most common/cost effective is copper (don't use the Aluminum/Copper combinations for this purpose). The bottom (chip contact area) should show a good polish - if you can see the machining marks, don't use it. The next step in the thermal treatment is the cooler fan, and here there are two approaches - one is the brute force method (very common) of having a hi-speed fan that blasts air through the cooling fins. This isn't always the best (especially for the thin-fin, close proximity heatsink designs) because the turbulence created by the fan and the fin design can seriously reduce the overall cooler thermal transfer characteristics - it creates "dead" areas that don't receive a good flow of cool air. The second approach is to use a lower speed, hi-volume fan which tends to move "larger chunks" of air at a lower speed through close-proximity fins more efficiently - it's also noticably quieter. Finally you need to consider the air exchange of your whole "box" - the suggestion offered by Ironbender can help considerably, but you don't need to cut additional holes if there are additional fan positions available. Here you need to fully evaluate the case, like:
1. Is it large enough - micro cases always present a substantial cooling challenge.
2. A case with a hole & shroud on the left cover (just above the cpu cooler), however, a fan blowing into the cooler isn't always good - it generally screws up the function of the cooler fan.
3. Additional case fans - a rule of thumb for placement is to use them to evacuate the air when they're in proximity of another fan (don't blow air onto another fan) and to bring air into case areas that aren't affected by any fans.
4. Power Supplies with multiple low-speed fans are helpful - make sure that the PS isn't underrated - they get hotter as they reach peak capacity.

Here are some links to show you some coolers that work with your chip type (when installed properly - most installers pay little attention to this component and pass their bad choice problems onto the user).

1. Here's one
2. Another
3. And Another

One thing to keep in mind with all these thin-fin designs is that you'll need to keep the heatsink clear of dust buildup on a more regular basis than you would with other design types.

The stock fan/heatsink that comes with the Prescott chip is not nearly adequate. Info. Upgrading the CPU fan/heat sink is a heck of a lot cheaper than buying a new CPU. Be sure to use a good thermal compound such as Arctic Silver 5.

Thanks guys...that's just what I needed to know.

Alfons...it's a large case with plenty of room for air circulation and there's a 450W power supply (at least I got that one right when I specified the system ).

I'll investigate the cooling options. The stock fan is so noisy as well, especially when it hits its max of 5,700 RPM.

Just one more question: if I want to take out the Prescott and replace it with a Northwood or Willamette (both of which are compatable with the mobo) is it relatively straightforward? I have three old mobos that I can practice on so I don't screw things up. I just hate this Prescott.

QUOTE (HKEd @ Aug 10 2005, 07:00 PM)

Thanks guys...that's just what I needed to know.    Just one more question: if I want to take out the Prescott and replace it with a Northwood or Willamette (both of which are compatable with the mobo) is it relatively straightforward?  I have three old mobos that I can practice on so I don't screw things up.  I just hate this Prescott.

Replacing the CPU is pretty straight forward. The key is to proceed with care and a little tenderness so as not to bend any pins. Nothing needs to be forced. Also, no fingerprints on the CPU or contact surface of the heat sink. I use a pair of my wife's surgical gloves.

Cheers, Tecumseh...appreciate the advice.

QUOTE

when it hits its max of 5,700 RPM

I am using a 7,200 RPM cooler, currently running at 6,900... not soo noisy

In fact, if it is anything like AMD chips, it's a ZIF (Zero Insertion Force) design. It will only go in one way, no other. Just sit it on the mounting board, and it literally falls into place. HERE is a good tut with pictures. You have the lever pointing up, insert the chip, and the lever locks down. Done.

Mounting the heatsink/fan can get dicey. There is an excellen tut on applying the grease HERE from Arctic Silver, but the information can be applied to any brand grease. I like to make mine about the thickness of a sheet of paper.

When attaching the heatsink, insert the hinge on one side, hold it up and clear of the grease on the chip, line it up and set it down once. Try not to wiggle it once seated, then use a screwdriver to lock down the other side. Done.

The Intel CPUs also use a ZIF connector, so that part is easy and even the alignment is easy - just look at the pin layout and match it to the connector, place it into the connector & lock it in. Now you should pay attention to installing a good cooler properly & when this is finished, you're done. Your MB probably is set for Auto Detection of the Chip, but if not, read the Manual to get the BIOS settings for frequency etc & after that it's all transparent to the OS and Apps.

Strange how there can be so many different operating temperatures to processors. Tends to make one believe that some hotter ones are because of poor design. Mine is a Pentium 4 Hyper-Threading 3.0gHz with 800 mHz FSB, using a stock fan and heatsink, yet I've never seen the temperature go above 51° C.

I agree, Jim. I can't begin to tell you how many dozens of hours and heatsink/fans I have swapped out trying to make a certain chip run cooler. I got a workbench drawer full of them, literally. I'm lucky if I get 2 or 3 degrees difference. Finally I realized that as long as the chip remains within tolerences it will operate fine for years.

Jim, to the best of your knowledge, have you ever directly known a chip that literally overheated and burned out? In the years I have been doing this I never have, not one. Nor do I know directly of anyone that it has happened to. I'm not saying this has never happened, of course it has. But I think the danger is exaggerated, IMHO.

I've never encountered anyone having that problem. I did have a fan quit on me once a couple systems back, but since I'm an avid Intel user, it just slowed the system to a crawl, then stopped. Replacement put it all back in good order again.

Never seen that also... not on overheating. I've seen many processor burned by power surge problems, like lightnings, or by short-circuit but definitely never due to a fan/cooler failure.

Interesting! I know that Intel has a shut down procedure built in for the chance of overheat, but AMD must have something also. For example, if a heatsink is attached with no thermal grease applied, OR the heatsink is crooked and not making contact, the unit shuts down immediately on start. So it must detect some kind of overheat, I would think.

Actually AMD included a termal diod in the core the same time Intel did... just took manufacturers of Motherboards a few months to start using the feature... That is why it took longer for the protection to start work on Athlons... (guess Intel made their own chipsets for motherboards)


Today both Intel and AMD cpus have protection from overheating... and as of lately AMDs cpus seems to run a tad cooler than Intel cpus... that might change with the next batch though... everythig changes...

/LinuxSam

Thanks again for all the replies. I'll let you know how it goes.