nehalem in the desktop

[dmens]

well finally i have a nehalem desktop up and running. i spent 4 hard years working on this cpu so it's a good feeling.

http://img267.imageshack.us/img267/8601/nhmam7.jpg

using a Noctua NH-U12P SE1366 heatsink so the temps are decent. i know the part i have can hit much higher clocks at 1.4V but my room is warm enough already. i haven't even tried lowering the core voltage, i suspect i can be stable at 3.8ghz even with 1.12V or so from what i have observed with this batch and still have safe headroom.

can't be bothered overclocking the uncore or running the RAM faster since i have cheap g-skill memory... having an unlocked part is nice because it lets me get away with low voltages everywhere except for the cores.

rounding off this system is a x25 intel SSD, arguably even more of an upgrade than the nehalem for everyday use.

also, notice how real temp gets the frequency wrong. heh.

===================================

update: vcc down to 1.14V, still 3.87ghz and rock stable.

too bad uncore is stuck at 1.2V, i'd lower that too

 

[Idontcare]

Damn that's some nice Vcc at load for that kind of GHz.

I've noticed no one has been bitching about Vdroop with these X58 boards, is it just non-existent with these particular mobo designs or are people being more reasonable about letting sleeping dogs lie?

I take it you've sent your expected "mad props" homage emails to Francois, thanking him for letting you watch him carry the majority of the workload burden during those four years? OK, that was a little low, I'll leave the Francois jokes behind me from now on.

Regarding the uncore clocks...I understand what you are saying about not increasing the clockspeed as you feel your ram will be the rate-limiter in that process, but what about going the other direction (downclock it a couple notches) and generate some data to give us a feel as to the performance impact that asynchronous L3$ has on system performance?

If downclocking from stock 2.67GHz to something like 2.33GHz or 2GHz yields a negligible decrease in benches then that would tell you it is kinda pointless to worry about overclocking it as well. Or vice versa would be good to know too as that would add a skosh of justification to buying those premium DDR3-1800+ low-voltage kits.

 

[dmens]

in regards to vdroop, i think it is going unreported. i'm not exactly sure where the voltage reading is coming from with a C2D, but the fact that with x58/nhm the readout is rock stable means it is just reading out whatever voltage you have the BIOS set to. im sure the cores themselves are receiving less voltage than that value.

i don't think the RAM will be the limiter, im just lazy and i don't do anything where the uncore or memory will ever be a roadblock, like workloads that use the queues heavily. the L3 is not asynchronous, just that when you increase the uncore frequency, the latency in terms of core clocks will be reduced. the uncore cycle latency is fixed.

anyways, im not sure what programs out there are good for uncore benchmarking. what is core load light and memory/core talk heavy? from what i hear, ddr-1066 was considered adequate for just about any desktop user, but not for servers. so maybe i can do that experiment with one of those workloads.

 

[roid450]

Wait, so you spent 4 yrs working on the CPU, when it just came out? am I missing something? :Q :Q u work for intel?

 

[dmens]

oh yes, intel pwns me. do i need a disclaimer?

 

[Idontcare]

Originally posted by: dmens
the L3 is not asynchronous, just that when you increase the uncore frequency, the latency in terms of core clocks will be reduced. the uncore cycle latency is fixed.

You would know better than me (or Anand), but I was just going by what Anand posted in his i7 review:

Multiple Clock Domains

The CPU operates on a multiplier of the QPI source clock, which in this case is 133MHz. The top bin Nehalem runs at 3.2GHz or 133MHz x 24.

The L3 cache and memory controller operate on a separate clock frequency called the un-core clock. This frequency is currently 20x the BCLK, or 2.66GHz.

http://www.anandtech.com/cpuch...howdoc.aspx?i=3448&p=2

I read this to imply the L3$ is running asynchronous to the core clockspeed when using an i7 940 or 965. Similiar to the asynchronous L3$ situation on Phenom.

I'm not so much interested in knowing the peak/optimal worst case scenario as to how detrimental the 2.66GHz L3$ is to the i7 965, just curious if in general apps are impacted in the sub-1% category or if this is a 5% performance item.

FPS in cpu-limited games, maybe a winrar bench or a pov-ray test. Anything really would be better than the total lack of benching to date on tweaking the uncore part of the i7.

 

[dmens]

yeah he got it. everything is a multiplier of BCLK, and you have your core and uncore multipliers. the L3 is still a synchronous design, it's just that you can run it at a different frequency compared to the cores.

i dont think winrar has a lot of core intertalk, and pov-ray is embarrassingly parallel. ill ask around tomorrow for suitable uncore codes.

 

[JMapleton]

Nice system, why block out the stepping name in cpuz?

 

[Zap]

Originally posted by: JMapleton
Nice system, why block out the stepping name in cpuz?

Maybe it is an ES?

 

[dmens]

yes it is ES

 

[pm]

Originally posted by: dmens
rounding off this system is a x25 intel SSD, arguably even more of an upgrade than the nehalem for everyday use.

Congrats on your system. Looks nice.

Yeah, I agree. The X25-M is argueably more of an upgrade than the Core i7 for most people's every day use. It certainly makes a huge difference in the "peppiness" of the system - more than I can tell going from a fast CPU to an even faster CPU... right up until I need to encode some video anyway.

 

[aigomorla]

Originally posted by: dmens
oh yes, intel pwns me. do i need a disclaimer?

nah your chips went off NDA..

There is nothing you need to hide, because intel already launched that cpu.

You should ask IDC if i showed him a funky cpu today.

Im really confused right now about my chip.. And i think i just confused the heck out of him this morning too.

 

[magreen]

Congrats on your system, dmens. I bet you're relieved you can finally talk about Neha now too.

Great thread.
*remembers why he joined AT forums and lost interest in the others*

Btw, is it true what they said a year ago that Nehalem C would be the cat's meow?

 

[dmens]

Originally posted by: magreen
Btw, is it true what they said a year ago that Nehalem C would be the cat's meow?

WIP.

 

[magreen]

Originally posted by: dmens

Originally posted by: magreen
Btw, is it true what they said a year ago that Nehalem C would be the cat's meow?

WIP.

Gotcha. Hush hush, wink wink, nudge nudge. It'll do 5.8 GHz stock cooling, eh? Wink wink, nudge nudge. Has 12 cores with HT, you say? I won't tell, don't worry. Nudge nudge. Runs at negative 12C on stock cooling, eh? She's a real goer, eh? Nudge nudge.

 

[pm]

Originally posted by: magreen

Originally posted by: dmens

Originally posted by: magreen
Btw, is it true what they said a year ago that Nehalem C would be the cat's meow?

WIP.

Gotcha. Hush hush, wink wink, nudge nudge. It'll do 5.8 GHz stock cooling, eh? Wink wink, nudge nudge. Has 12 cores with HT, you say? I won't tell, don't worry. Nudge nudge. Runs at negative 12C on stock cooling, eh? She's a real goer, eh? Nudge nudge.

While dmens reply could have been a little less terse, I'm not sure what you expect an Intel employee who is not a company spokesperson to say about an unannouced product - particularly on a large public forum like Anandtech.


* Not a company spokesperson for Intel Corp.

 

[magreen]

Oh I know. I'm just adding a little levity.

 

[pm]

Originally posted by: magreen
Oh I know. I'm just adding a little levity.

Sorry, I thought you were honestly annoyed.

 

[Idontcare]

Originally posted by: dmens

Originally posted by: magreen
Btw, is it true what they said a year ago that Nehalem C would be the cat's meow?

WIP.

Were you a TI employee I'd assume this acronym meant "work in progress" as in it is still in development (which could mean test/debug/respin) but I do not know what WIP means in this context.

Does WIP mean walk in park? or something else?

Originally posted by: pm

Originally posted by: magreen
Oh I know. I'm just adding a little levity.

Sorry, I thought you were honestly annoyed.

Being a little bit annoyed with dmens is kinda a mandatory entrance exam in this sub-forum, its only natural.

:laugh:

Just kidding dmens, you knows we love ya around here. Not so convinced about the friendlies at AMDzone though

 

[magreen]

Nah, not annoyed, it was a play on a Monty Python sketch. Anyway, I don't mean to take up any more of the thread with this, so back to the smart people talking stuff.

:beer:

 

[dmens]

work in progress. i shouldn't spend so much time here.

i've gotten the troll itch lately for amdzone especially after the i7 release... can someone pm me a login?