Silly CPU cooling questions

[EvilManagedCare]

Please be gentle, I am rather new to cooling options and PSU issues and I apologize this may be a bit wordy. I just want to make sure I have everything covered. Anyway, I have an AMD 64 3700+ processor using the stock cooler. This replaced a 3000+ that had also used the stock heatsink and fan from AMD. Both of these fans seemed to make a strange noise, almost like it would rev up, then resume the previous speed. This would proceed while the PC is on. I do not have Cool n Quiet enabled, so I am surprised the fan seems to be varying its speed. I've run Sandra SiSoft and it periodically throws out warnings about the CPU fan, but I was told by some others on this forum to ignore it as it evidently will do that for fan RPMs below a certain amount. I have fan speed settings configured in BIOS to vary speed depending on temp. The strange noise occurs regardless of this being on or off.

I have had no system instability and my temps are not abnormally high. When I check the voltage readings in the BIOS, a couple of them will change by about 0.03 V (sorry, I can't remember the specific readings or voltage being measured). For example, the CPU voltage will go from 1.50V to 1.53V intermittently, usually like every couple of seconds. This PSU is of ample Wattage and is only under a year old. This strange phenomena has gone on since I put the system together last November.

So, I'm wondering a few different things:

1. Should I get a new PSU? (I'm inclined to say no simply because I'm not having any instability and my temps are still acceptable so the fans seem to be working correctly)

2. Is there an adapter that can plug in from the 4 pin connectors from the PSU to the 3 pin connector on the fan? I don't care if the fan slows down or speeds up based on temp, I just want it to cool the CPU properly and stop making that irritating revving noise.

3. Should I just get a third party CPU cooler?

Thanks in advance for the help.

 

[JBDan]

1. I dont think so. What psu do you have?
2. Yes. This "revving" noise is interesting...stumped me so far
3. Up to your wallet and what you want out of cooling your cpu (performance/noise/etc...)
The voltage changes you speak of that vary...that is normal. I dont know any Vcores that stick on one value. Are you running any kind of cpu "throttling" software at all? You have the fan speed setting in BIOS to vary it....but yet when you disable this feature it still varies the fan speed? Have you monitored the fan speed in BIOS or Everest to see what its doing under different conditions? CHeck these out...will look for your reply 🙂

 

[EvilManagedCare]

JBDan, thanks for the reply, I'll have to try Everest. I'm unfortunately at work, so I can't do it until I get home.

As I think about last night I noticed the setting was for the CPU fan to be full at 40 C, and as it was revving, the temp was 41. I'm wondering if the temp keeps hovering around the temp at which the speed should be full, then it cools to under the temp and slows down again. If this is the case, perhaps a new CPU cooler is in order. I'm not running any CPU throttling software. There's a setting for this in the BIOS IIRC, what exactly does this do and what are the optimal settings?

 

[1Dark1Sharigan1]

Originally posted by: EvilManagedCare
As I think about last night I noticed the setting was for the CPU fan to be full at 40 C, and as it was revving, the temp was 41. I'm wondering if the temp keeps hovering around the temp at which the speed should be full, then it cools to under the temp and slows down again. If this is the case, perhaps a new CPU cooler is in order. I'm not running any CPU throttling software. There's a setting for this in the BIOS IIRC, what exactly does this do and what are the optimal settings?

I'm not sure what exactly what your referring to about fan speed an temps. Are you referring to the fact that you CPU fan is temperature-depedent because that's very normal . . . you can force it at 100% if you want (in bios is easiest)

Don't use Cool & Quiest if you're overclocking . . . it can cause errors . . .

 

[anandtechrocks]

I don't really understand whay you mean by saying the fans "rev up." Does this only happen at start up or does it sporadically happen during normal use? If it's just start up (like during the motherboard splash screen), then that is completely normal. If it is during regular use, that is probably because you are doing more CPU intensive operations which heat up the processor and thus require more movement of air (higher RPMs on the fan = more noise).

As far as 3 pin fans to 4 pin slots, I think they are backwards compatable. Just plug the 3 pin female into the 4 pin male (I don't remember which side should have the extra pin, but a wrong connection of a fan like that has never caused any damage).

I use an 3rd party CPU heatsink but that is because I like my computer really cool. It was totally unnecessary on my part, and I'm sure you'll be fine if you don't want to spend the money.

Oh yea, and with the voltage, you are completely fine. The voltage monitors on most motherboards are really f'd up if you want accurate measurements just buy a cheap multi-meter from Radio Shack that has an LCD screen (they are like $15, and if you want to know what to connect to what when testing your rails, just PM me).

 

[EvilManagedCare]

@ anandtechrocks: It's hard to describe the revving noise. But it sounds almost like a tiny motor starting up, then someone pushing the gas and it gets louder for just a sec, then back to it's "normal noise level. After reading the posts here and talking to others I think it's a product of the stock fan from AMD. I think my PSU is fine after what you are all saying with the voltage readings. The revving is more prominent during intensive use, so it is likely to be a product of the CPU being taxed; I was just surprised at how brief the bursts of added speed to help cooling were. It sounded almost as if something was wrong, like it wanted to reach a certain speed but just couldn't. After a year of this sort of thing I've never had a shutdown due to the CPU getting too hot.

@ Sharigan: You got what I meant. I can set the CPU fan to full for temps > X, where X is a temp of my choice. I believe it defaults to 40. Below that temp it runs more slowly and can be set to shut off at very low ones.

After all this, I think I may just get a 3rd party CPU cooler from Zalman if the noise continues to get to me. Or, if anyone has a suggestion for a quiet 3rd party cooler I'm all ears. The drawback on the Zalman is you have to remove the motherboard to put hardware on the back. If there's a quiet one that's easier to install I would like to know which one. I was thinking Thermaltake, but these are supposedly rather loud.

I appreciate the help.

 

[vanvock]

Have you tried upping the temp in BIOS that sets the full on temp? It may be that it's running right on the edge of 41 so if you increase to 45 maybe it will not spin up so often.

 

[potato28]

The XP-90 or XP-120 can go without fans. Zalman... if u get a Zalman get a 7000cu, or the 9500cu. And the Cooler Master HSF's tend to be quiet.

 

[1Dark1Sharigan1]

Yeah, get an XP-90C or SI-120 and pair it up with any quiet 120mm fan and you should be set

 

[anandtechrocks]

Originally posted by: potato28
The XP-90 or XP-120 can go without fans. Zalman... if u get a Zalman get a 7000cu, or the 9500cu. And the Cooler Master HSF's tend to be quiet.

Without fans?!? I would never use and XP-90 or 120 without a fan on an A64. Very bad idea.

If you want an 3rd party CPU heatsink, I really like my XP-90 but I did have to remove my motherboard to install it. To be completely honest though, it only takes 30-40 minutes to take out everything, install new HS, and replace everything.

If you want complete silence the Zalman 7700 Cu is great as is the XP-90. I think the XP-90 does a better job of cooling but is a little louder than the Zalman.