Recommended P55 boards

[Kindling]

I have Gigabyte P55A-UD5 and the board has both psu crackling noise and some idle "coil whine", similar to what digicat described above. Behavior seems identical with two PSUs: Seasonic S12II-430 and Antec CP-850.

Like everybody else, I can get rid of the crackling noise by changing the VCore manually - or by disabling C1E and EIST. Actually, the reason why adjusting VCore works on these Gigabyte boards is that C1E and EIST are set on Auto by default, and with that setting they apparently become disabled when the VCore is set to custom value. In other words, if I explicitly enable C1E and EIST, the crackling noise will return.

I've measured the wattage difference at idle, and it looks like there is about 5-10W increase in power consumption when C1E is disabled (I have i7-860), depending of course how much background activity there is in the system.

[Tyr Antilles]

Hi George7, this "buzzing noise when under full load" comes from the PSU or from other component? If is from PSU you can manually adjust the voltages in BIOS like Kindling said (except the part with C1E and EIST where I do not agree with him) and like I did (explained on my article here viewtopic.php?t=57310). If this is your case I don't think is normal. I also plan to keep my system for a very long time, that's why I tried to find the best way to keep it cool stable and with low voltages. Even I am not sure if the buzzing noise from the PSU is dangerous, I would suggest to take a look on my article or on similar articles over the net and try to solve it.


Welcome to the forums, Kindling. I think is a good way to share our problems here and try to find solutions in a constructive way .
Now...
I can't agree with "if I explicitly enable C1E and EIST, the crackling noise will return" because I did just that, adjusting voltage manually and explicitly enable C1E, EIST and all the other advanced CPU features and still I don't get any crackling noise, unless I set everything on auto - I get this noise only if I load optimized defaults or fail safe defaults from BIOS. So, it must be something connected with voltages not with advanced CPU features.

[Kindling]

Welcome to the forums, Kindling. I think is a good way to share our problems here and try to find solutions in a constructive way .

Agreed

I can't agree with "if I explicitly enable C1E and EIST, the crackling noise will return" because I did just that, adjusting voltage manually and explicitly enable C1E, EIST and all the other advanced CPU features and still I don't get any crackling noise, unless I set everything on auto - I get this noise only if I load optimized defaults or fail safe defaults from BIOS. So, it must be something connected with voltages not with advanced CPU features.

It is indeed connected with voltages, and C1E/EIST (Enhanced SpeedStep) are advanced CPU features that reduce CPU voltage aggressively and rapidly when processor is idle. For instance, SpeedFan reports as low as 0.86v with those features enabled. Maybe your overclocking setup prevents or greatly reduces this voltage adjustment, indirectly (perhaps it is simply the increased CPU voltage setting). Anyway, what kind of CPU voltage range are you getting, as seen with SpeedFan or similar software?

[Tyr Antilles]

As I wrote in my review I have:
- voltage set on BIOS manually - 1.131V as can be seen here: http://www.postimage.org/image.php?v=aVcI6dA
- on Windows I have 1.104V on idle: http://www.postimage.org/image.php?v=gxyC8lJ
- on full load I have 1.056V: http://www.postimage.org/image.php?v=gxyC5RA

The differences are because of the vdrop. Probably if you let the BIOS settings for voltages on AUTO you will get the crackling noise...

[Kindling]

- on Windows I have 1.104V on idle: ...
- on full load I have 1.056V: ...

It seems a bit weird that you have lower voltage when on full load. Voltage reducing features (C1E/EIST) don't really work here as supposed.

The differences are because of the vdrop.

Do you mean the VDroop / Load Line Calibration setting?

[Tyr Antilles]

Yes, I mean VDroop, sorry, from what I have seen on other computers with i5-750, this voltage behavior seems normal. This lower voltage happens because of the VDroop - because the CPU draws more power especially when is at 100% load, from what i have read.

[Kindling]

Right. At first I did try some non-default Load Line Calibration setting (since VDroop indeed sounded something that could make the difference) but it alone did not affect the crackling noise.

Anyway, the motherboard manual states this:

Note: Enabling Load-Line Calibration may result in damage to your CPU or reduce the useful life of the CPU.

Also, here's an interesting Anandtech article that covers Vdroop/Voffset:

http://www.anandtech.com/cpuchipsets/In ... i=3184&p=5

According to it, non-standard Load Line Calibration setting may cause unsafe voltage spikes in CPU. The weird bit about lower load voltage is also explained.

[Tyr Antilles]

Exactly, that's why I kept Load Line Calibration disabled and manually set on BIOS the voltage a little bit higher. From this voltage if you subtract vdroop results the minimum needed CPU voltage to run safe on Windows. Of course I didn't calculate anything, I just adjusted voltage, run a bunch of tests, adjusted voltage again, tests again... etc, till I found the lowest voltage for my desired overclocking frequency (3320 MHz), where the computer would be FULLY stable and yet cold and with minimum power consumption.

[Kindling]

Exactly, that's why I kept Load Line Calibration disabled and manually set on BIOS the voltage a little bit higher.

Ok, sorry, I misunderstood you there then... and also read the article too superficially it seems. Now that I test it, my system also goes to lower VCore under load (1.04v versus 1.1v on idle - setting in BIOS is about 1.1v). This is somewhat counter-intuitive to a person like me who doesn't have very good understanding of electronics. With all CPU settings at default, it was somewhat different situation: 0.86v at idle and 1.2v at load (if I remember correctly).

[deadrabbit]

Can anyone recommend a P55 mobo that has good automatic fan control in the BIOS?
I'm a noob when it comes to hardware tweaking, so I'm not entirely familiar with all the fan terminology . . . reading up on that now though.

I'll be running Linux on it, and I'd prefer to avoid dealing with fan control in the operating system.

[jtcb]

So half a month has passed since my last post and I still haven't decided on the motherboard. Can someone help me decide? Ask me questions. Do I really need USB3 and sata6?

As for the noise, I notice one poster is using P55-UD3 and there is no whine. All others are using the updated Gigabyte "A" version or Asus "E" version. Does it has to do with sata6 and usb3?

[Kindling]

Do I really need USB3 and sata6?

One thing to keep in mind that your ability to use those buses is a bit limited on the bandwidth-starved LGA 1156 platform. On Gigabyte "A" series motherboards, the USB3/SATA6g normally only uses bandwidth of a single PCI-Express 1X slot, which is pretty good for USB3 (even though not being able to fully utilize the maximum specs), but not so much for sata6. In Turbo-mode, the bandwidth is greatly increased by "stealing" half of the PCI-E 16X bus. Naturally this will affect gaming/3D performance by some amount, but looking at your choice of graphics card, this is probably a non-issue.

On all the Asus P7P55D-E boards, except the basic version, USB3/SATA6g is instead implemented by bridging bandwidth of two PCI-E 1X slots together. Better for high-performance gaming rigs, I guess.

As for the noise, I notice one poster is using P55-UD3 and there is no whine. All others are using the updated Gigabyte "A" version or Asus "E" version. Does it has to do with sata6 and usb3?

Probably not, since similar noise problems have been long reported with LGA 1336 motherboards. For instance:

http://forums.whirlpool.net.au/forum-re ... 39845.html

(though the above is about psu screeching noise, not whine)

Since at least in some cases the whine disappears at load, this has very likely something to do with the CPU power regulation circuitry instead.

In hindsight, I'd avoid enthusiast/overclocking motherboards for a silent computer. They tend to have more VRM components (among other superfluous things), and one could think that more components means increased chance for one that whines.

[Kreed]

Are there any motherboards or motherboard/CPU/PSU/Graphics card combos that don't result in coil whine or PSU crackling noises?

It would seem just about every board out there has this problem.