GA-880GM-UD2H: Help!!

[Krisbee]

After two weeks of dithering I finally upgraded my 5 year old AM2 PC with a new CPU/mboard/RAM combo. The PSU, drives etc remain the same.

CPU: AMD Phenom II X4 960T 95W BE (HD96ZTWFGRBOX)  with Hyper 212+
M/Board: GA-880GM-UD2H rev1.4 BIOS F8
RAM: 8GB (2x4GB) Corsair CMX8GX3M2A1333C9 at 1.6v
Videocard: GeForce 210
PSU: Seasonic SS-430GB

I mostly use Linux, but have loaded Win7 for the convenience of testing with CPU-Z , Hwmon, AMD overdrive and Prime95 etc.  

I don't game, and I don't intend to overclock or try to unlock cores. Why did I pick the Phenom II X4 960T then? Mostly because it was about the only Phenom Quad core still readily available at sub £100.

The build is up and running but I have several issues I need help with.  Going by published data,  I naively expected the CPU to operate between a Vcore of 0.825 and 1.475V, with CnQ scaling both frequency and Vcore.   I expected Turbo Core to work on up to two cores under certain loads and Vcore to then be at its max with two cores operating at 3400MHz max and two downclocked to 800MHz .  But this does NOT happen and I'm left puzzling over how this CPU interacts with BIOS of this m/board.

My issues are eluded to in these other posts:

http://forum.giga-byte.co.uk/index.php/topic,4763.0.html
http://forum.giga-byte.co.uk/index.php/topic,5998.0.html  
(I dont' understand Gigabyte's explanation)

Issue one is the extermely high default Vcore of the F8 BIOS.  On first post with default settings, the system voltages are on auto and while the normal CPU voltage is shown as 1.475V under the Tweaker page, it is an enormous 1.55V on the PC System Health page.  Load Windows 7 and Hwmon confirms that the Vcore is varying between 1.41V (min) and 1.55V (max). CPU-Z shows frequency varies with load and Turbo core works.  But surely 1.55V max is a crazy figure, given that this CPU is known to run at > 3GHZ for Vcore < 1.4V, and where's the 0.825V idle state?

Issue two is the fact that even with CnQ enabled, if Turbo Core is disabled then tests show that Vcore is fixed. CPU frequency varies under load, but Vcore is fixed as per your BIOS setting which is now 1.375V if system voltages are left on auto.  

So how are you supposed to get the CPU to run idle at the expected Vcore of 0825V? My answer so far is you cannot.  

If you use manual voltage settings for Vcore and turn off Turbo Core, the system may be stable under max load running at 3GHZ with a Vcore as low as 1.25V, but this is the voltage for all frequencies.  

Another strategy is to enable Turbo Core, but to set the CPB ratio to 15 hence the CPU will not operate about 3GHz.  Using manual voltage settings the normal CPU voltage can be dropped to 1.275V.  Tests show the system now runs idle at 800MHz with Vcore 1.12V and at 3000MHz with Vcore 1.28V.  So both Vcore and frequency appear to scale. But it still does not idle at 0.825V.

The strangest result is that with the last settings when prime95 runs CPU-Z reports that Vcore never goes above 1.14V!!!
See here:


 http://valid.canardpc.com/show_oc.php?id=2128009

What is going on?


My other issue is that my trusty Fujitsu FKB4725-202 keyboard (like the old IBM M) doesn't work in Win7. WTF?  

It's just as well I'm a Tux man.


PS The BIOS options include:

        Core Performance Boost
        Allows you to determine whether to enable the Core Performance Boost (CPB) technology, a CPU
        performance-boost technology. (Default: Enabled)
        CPB Ratio
        Allows you alter the ratio for the CPB. The adjustable range is dependent on the CPU being installed.
        (Default: Auto)
        Turbo CPB
        Allows you to determine whether to improve CPU performance. (Default: Disabled)

What is  Turbo CPB suposed to do? I've tried it  Enabled and noiticed no difference in system behaviour.

[Krisbee]

This PM I've had a chance to think about all this and had a quick look at both the AMD overdrive program and K10stat.

I believe I have a clearer understanding of what's happening and need to correct some of my previous post.

The published data about Vcore at CPU-world (and elsewhere) for the Phenom II x4 960T BE is at best misleading, if not actually incorrect. The range of voltage range of 0.8V to 1.4V is not the factory setting.

The default CPU p-states and corresponding CPU VID and frequencies are:

B0 1.475V 3400MHz
P0 1.325V 3000MHz
P1  1.325V 2300MHz
P2  1.325V 16000MHz
P3  1.325V 800MHz

This is shown by the K10stat program and AOD confirms the CPU VID for B0 and P0.  The bad news is this means there are effectively only two voltage states for this CPU, one for Turbo Core frequency and one for the rest.  Is this the same for Thuban Core CPUs?

When Turbo Core is enabled in the BIOS and the system voltage control is set to manual, the normal CPU voltage is shown as 1.475V.  As you might expect, this corresponds to the B0 CPU VID.  If  Turbo Core is then  disabled in the BIOS with the system voltage control is set to manual, the normal CPU voltage becomes 1.325V, corresponding to the P0 CPU VID.

There appears to be simple relationship between the CPU voltage in the BIOS with Turbo Core enabled and disabled of a 0.15V offset.  In my previous post I had set the CPU voltage to 1.275 with Turbo Core enabled and found the other frequencies to operate at 1.12(5)V in CPU-Z.  But I was wrong to say that both frequency and voltage scale. They do not.  CnQ only scales frequency, which seems a little pointless  if the power draw at 800Mhz is the same as for 2300Mhz, for example.

Also the Gigabyte statement in this post now makes perfect sense and explains the results of my earlier stability test.

http://forum.giga-byte.co.uk/index.php/topic,5998.0.html  

Incidently, where did gigabyte get the 1.55V for the BIOS setting when turbo core is on and sysem voltage control is auto?  That value is the maxium CPU VID for this CPU.

While the gigabyte BIOS for my m/board and AOD can help overclock this CPU, for someone who wants a cool and silent system things aren't so easy.  The fact that this CPU can operate at 3GHz with a Vcore of just 1.125V is impressive and it should really be able to idle at 800MHz at 0.8V or slightly lower.   But you can only get this by using K10stat or PhenomMRSTweaker.  It's a great pity AOD does not address undervolting and can only change the CPU VID of B0 and P0 on the fly.  

There is a Linux version of K10stat but I believe it's rather buggy.

PS My keyboard issue is fixed, the cause being a front USB connection that upset Win7.  

[agros]

Hello my friend, about 960T,

I naively expected the CPU to operate between a Vcore of 0.825 and 1.475V, with CnQ scaling both frequency and Vcore.  

All cpu's have such scales in their specs but I think you can't get that lowest limit. 0,82 core volt? how?
I was able to get 1.1V with Phenom2 720 via c&q. 720 has a scale 0.85-1.42V and same TDP(95) with 960T.
Now with 960T, c&q can't get it lower than 1.3V  
But in this link you gave me in the other post-->http://valid.canardpc.com/show_oc.php?id=2102831
someone has made it 1.23V ! Can someone tell us how he made it so?

About turbo boost, my opinion is that we dont need it, its useless. Gives you core voltage 1,475 for what? Disable it and you can easily o/c to 3.6-3.7GHz with default voltage. Default voltage with turbo boost disabled is 1.35V for me, you said its 1.32V for you... Maybe this detail depens on motherboard?

[Krisbee]

Hello my friend, about 960T,

I naively expected the CPU to operate between a Vcore of 0.825 and 1.475V, with CnQ scaling both frequency and Vcore.  

All cpu's have such scales in their specs but I think you can't get that lowest limit. 0,82 core volt? how?
I was able to get 1.1V with Phenom2 720 via c&q. 720 has a scale 0.85-1.42V and same TDP(95) with 960T.
Now with 960T, c&q can't get it lower than 1.3V  
But in this link you gave me in the other post-->http://valid.canardpc.com/show_oc.php?id=2102831
someone has made it 1.23V ! Can someone tell us how he made it so?

Most of the detials are in that diagram, the BIOS of the m/board used must allow good undervolting.

About turbo boost, my opinion is that we dont need it, its useless. Gives you core voltage 1,475 for what? Disable it and you can easily o/c to 3.6-3.7GHz with default voltage. Default voltage with turbo boost disabled is 1.35V for me, you said its 1.32V for you... Maybe this detail depens on motherboard?

I agree you don't need Turbo Core if your are overclocking, and yes the default CPU will vary with m/board.  In the diagram an Asus M5A99X EVO was used.  Check/ask at the ASUS forum to see how it's BIOS is setup and compare it to your own.

[agros]

"The default CPU will vary with m/board" with this cpu especially or with any cpu?

[Krisbee]

"The default CPU will vary with m/board" with this cpu especially or with any cpu?

I cannot answer youir question.  But I as I've said above with this CPU on my m/board and BIOS system voltages set to auto,  the CPU voltage is 1.55V? What's yours?

[agros]

I guess the answer is 'vary with any cpu'. Why this cpu be something special?

Mine is 1.475 if turbo boost enabled and 1.35 if turbo boost disabled.
I ve written that in the other thread, but for some reason you didnt read it

So you have 1.55 while i have 1.47... This means that your mobo is worse then mine, althought you said that yours is better.

[Steve66a]

"So you have 1.55 while i have 1.47... This means that your mobo is worse then mine, althought you said that yours is better." Hmmmm..... higher voltage does not always mean less efficiency

[Krisbee]

So you have 1.55 while i have 1.47... This means that your mobo is worse then mine, althought you said that yours is better.

Well argos, all I can say is you seem to be the one having trouble ...

[agros]

"So you have 1.55 while i have 1.47... This means that your mobo is worse then mine, althought you said that yours is better." Hmmmm..... higher voltage does not always mean less efficiency

Higher voltage for same result is not good, right?

Well argos, all I can say is you seem to be the one having trouble ...

My trouble is that I m worrying for the low limit voltage, but you have same trouble too because we have same cpu.