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Grant (SSSF) Send message Joined: 19 Aug 99 Posts: 13732 Credit: 208,696,464 RAC: 304 |
The place where I bought the machine has recommended AGAINST changing the CPU fan to an aftermarket one as it will blow air on to the mothboard rather than suck it away, causing more problems. Then we'll just have to disagree. Heatsinks that are designed for air to be drawn over or through them are very low profile- for use in rack mount server systems. Larger heatsinks require the air to be blown through them- doing otherwise reduces their effectiveness. Having hot air blown on to the motherboard may not sound like a good idea, but it's better that not having any air movement at all. The heatsinks surrounding the CPUs are designed to make use of the CPU fan to help cool them. Grant Darwin NT |
j tramer Send message Joined: 6 Oct 03 Posts: 242 Credit: 5,412,368 RAC: 0 |
what you need is something like this http://www.canadacomputers.com/product_info.php?cPath=8_135&item_id=036491 and find another computer shop to help you with your computer....heat/cooling is a major emeny of computers :) |
OzzFan Send message Joined: 9 Apr 02 Posts: 15691 Credit: 84,761,841 RAC: 28 |
Heatsinks that are designed for air to be drawn over or through them are very low profile- for use in rack mount server systems. Larger heatsinks require the air to be blown through them- doing otherwise reduces their effectiveness. Agreed, but the idea is for case fans to blow over any heatsinks on the motherboard. Preferrably a front case fan to pull in the air and a rear case fan to pull it out the back, all the while circulating the air over the motherboard and components. I still wouldn't want the hot air from the CPU being pulled over already hot components. As I said, doing so in my friend's case ended up costing her a motherboard and PSU. |
AndyJ Send message Joined: 17 Aug 02 Posts: 248 Credit: 27,380,797 RAC: 0 |
what you need is something like this These things are great for the price. I use this one: http://www.legitreviews.com/article/1292/1/ And yes, I agree. Find another shop. Regards, A |
j tramer Send message Joined: 6 Oct 03 Posts: 242 Credit: 5,412,368 RAC: 0 |
my next upgrade will be water cooling, with a chiller.....it wont make my beast faster, but safer :) |
SciManStev Send message Joined: 20 Jun 99 Posts: 6652 Credit: 121,090,076 RAC: 0 |
my next upgrade will be water cooling, with a chiller.....it wont make my beast faster, but safer Over heating will not be a problem. I love running water with a chiller. I have been running full out at over 4 GHz for 2.5 years, without getting the temps in the danger zone. Steve Warning, addicted to SETI crunching! Crunching as a member of GPU Users Group. GPUUG Website |
zoom3+1=4 Send message Joined: 30 Nov 03 Posts: 65740 Credit: 55,293,173 RAC: 49 |
The place where I bought the machine has recommended AGAINST changing the CPU fan to an aftermarket one as it will blow air on to the mothboard rather than suck it away, causing more problems. Fans bring air in help keep temps down, but If one has a filtered case, keeping those filters clean is important, at least every one to three months is what I do, It depends on the temps and the dust. The T1 Trust, PRR T1 Class 4-4-4-4 #5550, 1 of America's First HST's |
Grant (SSSF) Send message Joined: 19 Aug 99 Posts: 13732 Credit: 208,696,464 RAC: 304 |
As I said, doing so in my friend's case ended up costing her a motherboard and PSU. Something caused your friends system to fail- the CPU fan blowing onto the heatsink & then on to the motherboard wasn't the cause though. Grant Darwin NT |
OzzFan Send message Joined: 9 Apr 02 Posts: 15691 Credit: 84,761,841 RAC: 28 |
As I said, doing so in my friend's case ended up costing her a motherboard and PSU. Are you sure you're just refusing to allow the evidence to change your mind? Her system was overheating. The case was hot to the touch. Her first motherboard had signs of heat wear and tear. Her PSU literally burned out with a loud pop. The heat from the CPU used to flow up into the PSU which added to it's heat. Conclusion: the heat from the CPU blowing across the motherboard components and into the PSU caused a catastrophic failure. After replacing the failed components we upgraded her to an after-market CPU cooler that pulls the air off the CPU and a case with the PSU located at the bottom so that the hot air cannot flow up into it. Her case temps have been the lowest they've ever been. I've been building systems long enough, and I've built enough of them to know how to find the root cause of the problem. Her problems were purely heat related and it was due to blowing hot air across the motherboard and allowing it to flow into the PSU. |
KWSN THE Holy Hand Grenade! Send message Joined: 20 Dec 05 Posts: 3187 Credit: 57,163,290 RAC: 0 |
Dust may well be your problem, both on the CPU heatsink and on the GPU heatsink; it's an aftermarket item but here's what one of mine looked like after about 4-5 months 24/7 operation... Zalman fan-heatsink 8-6-11 by THE Holy Hand Grenade!, on Flickr For the record, this computer has a 120mm fan in front, an 80mm on top and the side, all blowing in, and 3 80mm's on the back (in addition to the power supply's fan, of unknown size) all blowing out. Another computer (with more hard drives...) has a 120mm and 3 80mm's in front and an 80mm on the side blowing in, and two 80mm's and the power supply fan blowing out in back. (there's also two uncovered slots in back... Neither computer has had heat issues (except when the heatsink gets clogged like the photo) . Hello, from Albany, CA!... |
OzzFan Send message Joined: 9 Apr 02 Posts: 15691 Credit: 84,761,841 RAC: 28 |
Dust may well be your problem, both on the CPU heatsink and on the GPU heatsink; it's an aftermarket item but here's what one of mine looked like after about 4-5 months 24/7 operation... Since people aren't using the 'reply' feature of the message board, I don't really know if this was meant for me or someone else it the thread, but assuming it was meant for me: I would have mentioned dust in my original description of the problem if it indeed was a factor. In fact, I have taught my friend how to open her case and blow out the dust using some canned air and she does so on a regular basis. So no, dust and air filters were not suspects in her issues or hardware failures. |
j tramer Send message Joined: 6 Oct 03 Posts: 242 Credit: 5,412,368 RAC: 0 |
i usually use a compressor to blow out the dust, and a vacuum to suck out the dust at the same time, to get rid of the junk.....houses with smokers are the worst.....yuckies :) |
Grant (SSSF) Send message Joined: 19 Aug 99 Posts: 13732 Credit: 208,696,464 RAC: 304 |
As I said, doing so in my friend's case ended up costing her a motherboard and PSU. Nope. Correlation isn't causation. Her system was overheating. The case was hot to the touch. During the build up here, all my PC cases have been hot too the touch. During the dry, they're just warm. Her first motherboard had signs of heat wear and tear. Her PSU literally burned out with a loud pop. Yep, PSU died. I've got that. The heat from the CPU used to flow up into the PSU which added to it's heat. Just like 100s of thousands of other computer systems around the world. Conclusion: the heat from the CPU blowing across the motherboard components and into the PSU caused a catastrophic failure. You may conclude that, but it doesn't make it factual. It could have been due to a faulty PSU fan. Failure of the PSU fan will cause the PSU & system to overheat- the PSU fan is the main device for cooling an ATX case. If things get hot enough the PSU will die. Dying PSUs can take out a motherboard & other components. After replacing the failed components we upgraded her to an after-market CPU cooler that pulls the air off the CPU and a case with the PSU located at the bottom so that the hot air cannot flow up into it. Her case temps have been the lowest they've ever been. To be expected. I've been building systems long enough, and I've built enough of them to know how to find the root cause of the problem. I have to say it- building a system & reparing a system are very different things. Her problems were purely heat related and it was due to blowing hot air across the motherboard and allowing it to flow into the PSU. Sorry, but i disagree. Millions of systems use that cooling method, year after year, without failure. The ATX cases were designed so that the PSU fan was responsible for cooling the system. The motherboards in such cases are designed to make use of the CPU fan to help cool their onboard regulators. And it works, as the systems around the wolrd still running prove. That would indicate there was ome other casue for the system failure- most likely the PSU fan being dead. Grant Darwin NT |
kittyman Send message Joined: 9 Jul 00 Posts: 51468 Credit: 1,018,363,574 RAC: 1,004 |
If everything is working as intended, almost all designs intend for the CPU cooling air, after cooling the CPU, to be then directed over the motherboard's surrounding heatsinks to remove additional heat from them. Unless something upsets the happy balance, that's the way they were engineered to work. Too much heat buildup indicates another problem.....perhaps too much load for a marginal stock cooling solution, fan failures, dust buildup, whatever. I have built every computer I ever owned from scratch, and have jettisoned the stock CPU cooling solution immediately on every one for over 11 years. If you are running 'closed case', most times you have to add or upgrade the fans that get the heat out of the case in the first place. Upgrading the CPU cooler without upgrading the case ventilation will only better circulate warmer air within the case. Mine all run 'side-off'...with added fans to coax the cooler ambient air to where it is required. Frequent 'dust bunny' (kitty fur) hunts are required......LOL. "Freedom is just Chaos, with better lighting." Alan Dean Foster |
Iona Send message Joined: 12 Jul 07 Posts: 790 Credit: 22,438,118 RAC: 0 |
I agree with everything you've said, Mark. I've been throwing together my own PCs for almost 20 years and really, it has only been since the P2/P3 that we've seen HSFs as being a standard item or a required item. Having said that, I used coolers on my 486s, as they ran at a then phenomenal 40 MHz FSB (yep, AMD CPUs...could'nt/would'nt run to the cost of the Intel ones!) and it gave me some latitude to do some OCing, which was pretty typical in those days. A CPU was literally an investment in those days, so one tended to get the maximum from that 'investment' - that meant cooling was needed. My big Scythe Ninja 2 is currently cooling my E8400, just as it did the E6550 before it and does a brilliant job....even with kitty fur clogging the output side of the fan, I've yet to see the CPU get to over 42C. True, I don't OC much, these days, but I did run a 10% OC overnight, once, and it still did'nt get over 40C! I don't use the supplied standard Scythe fan on the Ninja HS, as the Akasa Viper PWM fan, seemed a better bet and have used the Scythe fan as a case cooler, cooling the chipset area. I tend to think that the location of fans is of more importance. Fortunately for me, on my cheap and cheerful CoolerMaster Elite 331 case, the position for the rear exhaust fan, is directly behind where the CPU goes on my MSI board - thats ideal. Since then, I now use two fans, working push-pull as there is no room to fit a second exhaust fan - it works fine and I now only have to clean the 'external' fan as it is now the one that collects all the dust! When I changed graphics card, I've had to introduce extra cooling in one area, for the simple reason that the HSF unit on the GPU did not exhaust out of the case. There is a lot of trial and error, but even a very cheap fan thats lying around in the 'junk box' can make a big difference. So-called standard 'cooling solutions'? As far as I'm concerned, any system builder who puts together a system with marginal cooling capacity, is not worth dealing with.....their own incompetence could also nullify any warranty they provide, but would they even dare to tell you that? Happy crunching Don't take life too seriously, as you'll never come out of it alive! |
Wiggo Send message Joined: 24 Jan 00 Posts: 34744 Credit: 261,360,520 RAC: 489 |
In all the PC's that I've built myself over the last 15yrs have I never used a standard HSF but I have come across a few setups that must drawn air away from the mobo and that's in the case of those old poxie style mATX cases that had the PSU's cooling fan sitting within 0.25-0.5" (6-13mm) away, directly centered over the CPU fan and placed between the CPU and the side panel instead of in the usual old standard position (these must run that way or the HSF starves of air with the PSU fan sucking the air away from it). Cheers. |
OzzFan Send message Joined: 9 Apr 02 Posts: 15691 Credit: 84,761,841 RAC: 28 |
During the build up here, all my PC cases have been hot too the touch. During the dry, they're just warm. During the buildup? During the dry? I'm not familiar with these terms. Hers was hot because of inefficient airflow while running BOINC. The hot air off the CPU was blowing down toward the motherboard components and up into the PSU. This on top of the fact that there was a case fan directly over the CPU to pull some of the air out, and a front case fan pulling air in. Plenty of fans. Too much hot air. A new case and a CPU fan that pulls off the CPU have resolved the problem. I have to say it- building a system & reparing a system are very different things. /rolleyes Of course it could be implied that I've repaired them as well. If you can't understand implications, I'll say it point blank: I've repaired many systems over the years as well. You may conclude that, but it doesn't make it factual. Just because you disagree, doesn't make it factual or questionable. PSU was replaced twice. Both were high quality parts not known for their failure rates. Sorry, but i disagree. Millions of systems use that cooling method, year after year, without failure. The ATX cases were designed so that the PSU fan was responsible for cooling the system. The motherboards in such cases are designed to make use of the CPU fan to help cool their onboard regulators. And it works, as the systems around the wolrd still running prove. As you said, correlation isn't causation. Most other systems aren't running at full capacity 100% of the time like ours are running science apps. Sure, when the ATX formfactor came out, the Pentium II was just released, and cooling those CPUs didn't require much. AT cases never required the PSU to cool the system. There's no way a PSU should be expected to cool a system these days. That would indicate there was ome other casue for the system failure- most likely the PSU fan being dead. Well, you're partly right. The PSU was the second piece to be replaced after the motherboard. Yet the system was still overheating and she lost a second PSU (sorry, didn't mention that before). |
OzzFan Send message Joined: 9 Apr 02 Posts: 15691 Credit: 84,761,841 RAC: 28 |
If everything is working as intended, almost all designs intend for the CPU cooling air, after cooling the CPU, to be then directed over the motherboard's surrounding heatsinks to remove additional heat from them. Unless something upsets the happy balance, that's the way they were engineered to work. Maybe back in the days of AT formfactors, sure. Back then the CPU was placed in front of the case, with an optional front case fan blowing across the CPU's heat sink and then onto the rest of the components. This air was typically not very hot in those days. Since the ATX design, the CPU is typically located to the right of the components, and for a long time directly under the PSU to assist with cooling. Once CPUs became too hot, an active cooling solution (CPU fan) was required. The optimal placement of this fan is to pull the air off the CPU directly, while placed right under a rear exhaust fan to pull the hot air out immediately, with a little assistance from the PSU. Now with our multi-core CPUs crunching BOINC 24/7, running our CPUs as hot as they can be, it's even more important to get the hot air out as quickly as possible. This is why a front case fan is so important to blow cool air over the motherboard components, and to be pulled out the back via the exhaust fan as well. If the ambient temperature gets too hot inside the case, then there's an obvious problem. With sufficient cooling fans, the hot air from the CPU should never be blown over the other components. Even if it is active air cooling, the heat is simply too much for the components to handle. This is why a front case fan is far more effective than a CPU fan that blows onto the CPU and across the components. Too much heat buildup indicates another problem.....perhaps too much load for a marginal stock cooling solution, fan failures, dust buildup, whatever. I've never had to use a third party solution for any other AMD, Intel or VIA (Cyrix) CPU in the past. Typically the one included has always been sufficient. Too much load, certainly. Running BOINC on a Phenom II X4 can get it quite hot. There was a PSU fan failure that took out the first PSU. It was replaced. Then the motherboard went out. It too was replaced. Then the PSU went out again. Dust wasn't an issue, nor any other buildup. She's very good at keeping the inside of her case clean. Hers was the only system I've ever built with the CPU fan blowing onto the CPU and across the components. The last piece we replaced was the CPU fan with one that pulls the air off the CPU, and the system has been running as smoothly as ever. I have built every computer I ever owned from scratch, and have jettisoned the stock CPU cooling solution immediately on every one for over 11 years. If you are running 'closed case', most times you have to add or upgrade the fans that get the heat out of the case in the first place. Upgrading the CPU cooler without upgrading the case ventilation will only better circulate warmer air within the case. I've been building systems for over 25 years, and I've never had to replace the stock CPU fan when it comes with one. It has always been sufficient. Could it have been better? Yes. But it was sufficient. As for case fans, I've always used high quality, maximum airflow fans. Upgrading them simply because I'm upgrading the CPU fan would be a waste of money. |
kittyman Send message Joined: 9 Jul 00 Posts: 51468 Credit: 1,018,363,574 RAC: 1,004 |
Of course, we could agree to disagree......... "Freedom is just Chaos, with better lighting." Alan Dean Foster |
OzzFan Send message Joined: 9 Apr 02 Posts: 15691 Credit: 84,761,841 RAC: 28 |
Of course, we could agree to disagree......... I don't understand what there is to disagree with though. Is it really that hard to accept that perhaps blowing the air onto the CPU while spreading the hot air across components is a bad idea? |
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