Share your Opteron experiences TDP/Stepping - OC/Undervolt

[Hifriday]

I recently purchased a s939 dual-core Opteron (before they're finally retired) hoping to luck out with a 35W TDP chip. Compared with my current 44W TDP single-core chip, the new chip should consume less power and generate less heat even with both cores loaded. I had to settle for a more expensive 170, as unfortunately they don't carry the better valued 165s. The stepping is CCBBE which in general seem to be excellent overclockers with quite a few reports of hitting 2.7-2.8ghz at stock Vcore. My thinking was that a chip that could overclock so well without voltage increase most probably also underclocks well.

I installed the chip and ran Tcasemax, unfortunately my heart sank when a 85W TDP was displayed. Now I'm thinking, maybe the chips that overclock so well do so because of their ability to draw more power. In order to reach a high clock speed, a sufficient amount of power is necessary. Therefore if a chip is already pulling enough current (ie. those with high TDP) then no Vcore bump is needed (hence the high clocks on stock voltage). That would also mean low TDP chips (like the wonderful 35W TDP I would love to get my hands on) should be pretty bad overclockers as even with Vcore bumps they have a hard time pulling enough power.

If that's correct, then the good overclock steppings should have high TDPs and bad overclock steppings low TDPs (assuming that within each stepping, TDPs are similar). Unfortunately most user postings on their Opterons either list the stepping or the TDP, but rarely both so it is hard to see if there is any truth in this thinking. However I'm hoping enough SPCR forum readers have had experience with these Opterons and can share TDP, stepping, and overclock/underclock experiences, and their take.

From xtremesystems Opteron thread there is a collection of stepping/overclock data where most of their CCBBE and CCB1E steppings reach 3ghz or more and many of the CCBWE steppings being poor overclockers.

My experience using an ASUS A8N-VM CSM mb and PW200M DC-DC PSU (power figures = AC Consumption with loading via Orthos)

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Opteron 170
CCBBE0615DPMW
85.0W TDP

STATE        Clock   Vcore   Idle- Load
STOCK        10x200  1.35v   68W - 117W  
UNDERVOLT    10x200  1.15v   59W - 97W
UNDERCLOCK    5x200  0.90v   50W - 66W
OVERCLOCK    10x240* 1.35v       - 128W
OC/UV        10x240* 1.25v       - 113W

*240 is the maximum clock rate on this mb, and since this chip easily reaches it even undervolted, I'm guessing it should be a decent overclocker on a more capable mb. Hehe any overclockers with a 35W chip wanna trade!?

For comparison, the single-core Opty 144 (44.1W TDP) it replaced ran about 7C cooler.
IDLE 5x200 0.80v 50W
LOAD 9x200 1.00v 63W

[Bubbalobill]

AMD64 TCaseMax - v1.19
----------------------
Processor: AMD Opteron 146 (San Diego)
CPU Speed: 2009.13 (200.91 x 10.0)
Revision: SH8-E4
Platform: Socket 939
Startup VCore: 1.400v
Maximum Case Temperature = 55C
TDP: 38.2 Watts

Just my tribute, a CAB2E, not really tried to overclock it much.

EDIT: Is there really no Cool ´n Quiet on Optys?

[ryboto]

opterons support cool n quiet, although, it's called "power now"...it works exactly the same. I've got an opteron 170, for some reason my motherboard wont let me use the 10x multi above an fsb of 267mhz. Currently I use two power states, 2.8ghz (9x312) 1.4v(although cpuz, core temp, and crystal cpuid all say that it's 1.35v) and 1.25ghz(4x312) at 1.025v.

Tcasemax says mine has a tdp of 85W.

[skj]

Well, I just bought one of those coveted 35 watt Opteron 180s as an upgrade from an Athlon 64 3500+ Winchester chip. Given what I've measured, that 35W seems meaningless. Here's the stepping, the TDP reported by TCaseMax v1.19, and the overall system power consumption measured with a Kill-A-Watt at the wall.

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Opteron 180
CCBWE0550MPMW
35.0W TDP

200x12	1.350V	171W Load - STOCK
200x12	1.275V	156W Load
200x12	1.225V	147W Load
200x11	1.150V	129W Load

Bear in mind, I'm running other power-hungry components that affect my overall power consumption. But compare the figures above to what I measured for my 3500+ and you can see the extra power draw from this Opteron CPU.

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Athlon 64 3500+

200x11	1.400V	119W Load - STOCK
200x11	1.200V	104W Load

At stock speed and voltage, this 35W Opteron draws 52 watts more than my old 3500+!

[Hifriday]

Bear in mind, I'm running other power-hungry components that affect my overall power consumption. But compare the figures above to what I measured for my 3500+ and you can see the extra power draw from this Opteron CPU.
...
At stock speed and voltage, this 35W Opteron draws 52 watts more than my old 3500+!

Are both CPUs measured in the same system running the same components? Also same RAM settings? That doesn't really make sense that the 35W Opteron is drawing so much more power than your 3500+ Winnie!? Just double-checking, is your Tcasemax reading 49C?

As for an update on my 89W Opty 170, indeed it does overclock very nicely. I threw it in a DFI LanpartyUT NF4-D mb and it readily ran 2.8ghz stable at stock vcore. Anything higher required a bump in vcore to be stable. Total system draw (with a 7800GT) reached 180W under Orthos and 240W running 3Dmark. Further perusing on OC forums, it does seem that in general OCers have also found high TDP chips tend to overclock better.

[Lawrence Lee]

Can't get my Opteron-165 to 2.6Ghz unless I increase vCore to 1.425 (IRC - it's been awhile), so I just have it at 2.5Ghz, stock voltage on a DFI Ultra-D.

[Hifriday]

That seems to fall along the trend that low TDP chips tend to need more voltage to reach higher clocks, although certainly a 40% OC at stock volt is already pretty good. Have you tried undervolting your chip, will it run nicely at lower vcore stock clocks? Also noticed you're using a 4x multiplier, both my 144 and 170 never liked this multiplier. I'm guessing your chip runs relatively cool for a 2.5ghz processor even under load?

[Bubbalobill]

opterons support cool n quiet, although, it's called "power now"...it works exactly the same. I've got an opteron 170, for some reason my motherboard wont let me use the 10x multi above an fsb of 267mhz. Currently I use two power states, 2.8ghz (9x312) 1.4v(although cpuz, core temp, and crystal cpuid all say that it's 1.35v) and 1.25ghz(4x312) at 1.025v.

Tcasemax says mine has a tdp of 85W.

I can´t work out how to get this "Power Now" function to work, it runs at stock speed at all times no mather how I try. I´ve enabled it in BIOS and the same setting in "Power management" (or what it is called) as I used on my previous Winchester, but no go.
Any thoughts?

[nici]

Opty 165 running at 2600mHz on 1.3V, it easily does 2800 on 1.4v but is obviously hotter then. I can boot into windows at over 3gHz, but when i tried that the 9500 could not handle it. That was at over 1.5V volts though, and i dont see any need to run it that fast anyway.. Wel maybe to prove what a 300W PSU can run and post it on DFI street It could work wiht my Ninja and 190CFM Delta

IIRC the TcaseMax is 59 and the TDP 85, stock VID is 1.350V.

Oh i have a nF4 Ultra-D, and i dont have the extra power conenctors in place. just the normal 24 and 4-pin connectors.

[sjschwinn]

opterons support cool n quiet, although, it's called "power now"...it works exactly the same. I've got an opteron 170, for some reason my motherboard wont let me use the 10x multi above an fsb of 267mhz. Currently I use two power states, 2.8ghz (9x312) 1.4v(although cpuz, core temp, and crystal cpuid all say that it's 1.35v) and 1.25ghz(4x312) at 1.025v.

Tcasemax says mine has a tdp of 85W.

I can´t work out how to get this "Power Now" function to work, it runs at stock speed at all times no mather how I try. I´ve enabled it in BIOS and the same setting in "Power management" (or what it is called) as I used on my previous Winchester, but no go.
Any thoughts?

You have to set the windows control panel power managment function to "No Management" (or something similar) - did you try that?

[ryboto]

I can´t work out how to get this "Power Now" function to work, it runs at stock speed at all times no mather how I try. I´ve enabled it in BIOS and the same setting in "Power management" (or what it is called) as I used on my previous Winchester, but no go.
Any thoughts?

You have to set the windows control panel power managment function to "No Management" (or something similar) - did you try that?

you may have to uninstall the driver if you had it for the winchester. If you go to AMD's website, they have an opteron driver/utility section. Download the power now driver for xp, install, restart. Make sure cool n quiet is enabled in the bios, boot to windows, and in the control panels power management, set it to "minimal power management". There are also MS dual core hotfix's that might help if what I suggested doesn't. I've never had to use them though.

[Hifriday]

Hi Ryoboto, Amourek, Nici,
What is the stepping of your chip? Just wondering if we can find a trend here. Also any more undervolting experiences? So far for the dual-cores we have:

85W TDP (3 samples)
Steppings: CCBBE0615DPMW(1), n/a(2)
OC: all run 2.8ghz with 1.35-1.40v
Undervolt: [email protected]/[email protected], [email protected], [email protected]

35W TDP (2 samples)
Steppings: CCBWE0550MPMW(1), n/a(1)
OC: one not stable past 2.6g unless bumped beyond 1.4v
Undervolt: [email protected]/[email protected], [email protected]?


As for Cool'n'Quiet, it worked without downloading any drivers on a clean install of Windows XP-SP2, but that may depend on the mb. However using a utilitiy like CrystalCPUID serves a similar purpose but allows better control and undervolting and/or underclocking.

[ryboto]

Hi Ryoboto, Amourek, Nici,
What is the stepping of your chip? Just wondering if we can find a trend here. Also any more undervolting experiences? So far for the dual-cores we have:

85W TDP (3 samples)
Steppings: CCBBE0615DPMW(1), n/a(2)
OC: all run 2.8ghz with 1.35-1.40v
Undervolt: [email protected]/[email protected], [email protected], [email protected]

35W TDP (2 samples)
Steppings: CCBWE0550MPMW(1), n/a(1)
OC: one not stable past 2.6g unless bumped beyond 1.4v
Undervolt: [email protected]/[email protected], [email protected]?

I see you put my undervolt in there. My core stepping is CCBBE0615EPMW. I haven't tried any undervolting with the stock fsb, but I do know it works at 2700mhz with stock vcore(1.35v).

[skj]

Are both CPUs measured in the same system running the same components? Also same RAM settings? That doesn't really make sense that the 35W Opteron is drawing so much more power than your 3500+ Winnie!? Just double-checking, is your Tcasemax reading 49C?

I'm with you, but the CPUs were measured in the exact same system. Only the processors changed.

I didn't include these measurements in my first post, but here's a more direct comparison. The 3500+ at 2.2GHz and 1.2V pulled 104W. The Opteron at 2.2GHz and 1.2V pulls 135W. That's a 31W difference at the same speed and voltage.

I guess I can can accept that a CPU with two cores and four times the cache would run hotter than my old processor. I was just a little disappointed.

My TCaseMax reading is 49C.