Intel Core i7 Thread

[magneticman]

I've been waiting for someone to make one of these threads (I guess many people still aren't impressed + price) so I make this now. Plus I need help with the overclocking

Been a while since i've delved into overclocking on core 2, so i spent the past couple of days messing about. Managed to get 3.8ghz within a minute of changing settings but can't get it to stabilise over 4.0ghz, and even then it requires vcore to be at 1.5v (for me) just so Windows can boot.

I managed to run superpi at 4.2ghz (1M done in 10 seconds flat ) though; after you reach such greatness I don't feel like settling for less lol. I've seen many examples of people getting 4.0ghz on the same board with a lower vcore and crapper heatsinks so i'm a bit annoyed. I think i'm going to have to look at extra cooling if it's possible (and PSU?), though I don't see many other options for my case.

Benchmarks were pretty interesting (it decimated other cpus), i'll post pics later if anyone cares.

Anyone else with i7s out there want to chime in?

[moogle]

Anyone else with i7s out there want to chime in?

Sure .....



















In 6 months to a years time

But seriously 1.5v for 4GHz boot stable isn't looking good. I thought these ones could do better overclocks on less volts. Do post up some 3DMark06 benchmarks though
I would like to see how much faster it is than the previous gen CPU's

[this_is_gav]

It's gonna cook the CPU in no time at 1.5v. 1.4v is considered a lot on good water cooling... 1.35v seems to be considered the max on decent air at the moment.

Had a nightmare of a time with mine (i7 920, Gigabyte UD5 + 12GB Corsair DDR3 1333 D9). Thought I had a duff board, as it clocked well at 3.7GHz without tuning (got a quite air cooling setup, so don't see much point in pushing any further), but when you shutdown and then switched on again, it booted twice, the 2nd putting the clocks back to stock due to a failed overclock, despite being Prime stable for 2 hours. Spent 2 days working out what was wrong, but couldn't test the RAM as memtest86+ won't boot at the moment. Not until consistent BSODs and subsequently losing 2GB of RAM did I realise what was going on. Thought it was a dead DDR3 slot, as swapping RAM around made little difference, but it's a dodgy stick it seems. Never seen a stick fail to report under the BIOS/Windows before, while still being listed in CPUz. Down to 10GB at the moment, and presumably in single channel mode until I get an RMA started on Monday.

[magneticman]

unlucky there, rma'ing is quite annoying.

How is the UD5? I was thinking of going with gigabyte again but thought i'd go with Asus this time, all of the better results are on the Gigabyte or Asus at the moment. Still playing around with the features new to me though, wtf is cpu pll and loadline calibration

something funny has happened now though, whereas before I couldn't get 4ghz+ stable even during 1.5v (about 4 seconds in prime lol), i'm now running 3.8ghz at 1.3v and it's solid. go figure.

on 3dmark06 i got 7000+ (3.9 i think) before but I forgot to bookmark the link, i'll run benches again later..

[GSte]

If you leave speedstep enabled, the turbo thing will up your multi to 21 which should give you a little more..... have you had a play with differential amplitude? I found it helped a bit at 3.9GHz setting it to 800mv.....

[moogle]

wtf is cpu pll and loadline calibration

Stuff that was there on the previous gen boards

LLC is to keep the voltage near the same under load and PLL is something else which I still haven't figured out I think. Was that 7000+ score on the CPU score or something else?

[magneticman]

yeah i got to 4.2 using turbo, but not very stable

how did you turbo and set the bclk to 195 btw? I can't do both unless i'm missing something :S

*yeah but my previous board didn't have stuff, hence i said "new to me"

and yeah just the cpu score was in the 7000s, I just did a vantage test too:



the gpu score is diabolical in comparison lol

[GSte]

how did you turbo and set the bclk to 195 btw? I can't do both unless i'm missing something :S

Erm.... make sure you leave Speedstep enabled. Change the OC mode to "manual" and you can just change the Bclk and leave turbo mode enabled.....!?

[magneticman]

yeah i'm stupid, i just saw while i was tinkering again lol

[strike-down]

The CPU PLL(Phase-Locked Loop) (afaik) determins the frequency of the CPU. (It works like a quartz crystal in a watch.) The CPU frequency comes from clock generator PLLs, which multiply a lower-frequency reference clock (usually 50 or 100 MHz) up to the operating frequency of the processor.
Thats just off the top of my head, but there are bound to be many websites that can explain it better than I have

[Fornowagain]

Lots of 920 users are having issues with x20 multiplier. You may find the x19 with a higher BCLK gets you more MHz. Core PLL is a reference voltage, set it around 1.85v for 4GHz 920. LLC is load line calibration, its suppose to remove the vdroop and its not working properly on the UD5, at least not 100%.

What's the rest of your voltages and multipliers for uncore and QPI etc?

[magneticman]

at the moment it's:

multiplier: 19x
uncore: auto
qpi: auto
bclk: 201
ram: 1610mhz

vcore: 1.3v
vuncore: 1.35v
dram voltage: 1.66v
cpu pll: 1.9v (i think)
llc: on
both spectrums: off

at the moment's it's stable-ish, and the temps are the coolest so far (37-38c idle), quite close to temps at stock actually. But from 3.9 onwards it can't run prime95 for more than 5 seconds :S

[Fornowagain]

Certainly nothing obvious there. Set the QPI multi as low as possible, x18. The uncore multi to twice (or more) than the memorys, so x16. Its been recommended the Vuncore (QPI/Vtt) should 0.05v less than the vcore.

[Robscure]

The Rampage mobo is having memory compatibility issues, maybe your boards are also suffering the same fate.

Read more here.

Excerpt: "One note of interest is that we had several problems with our Rampage II Extreme board in regards to memory compatibility and overclocking. The 0602 BIOS certainly improved the situation but ASUS has updated the board and retail units will incorporate the latest component updates."

As far as overclocking is concerned, intel's suggestions...

"Keeping VCore, VDimm, and VQPI in proper sync is the key to a stable overclock at voltages that will not shorten your processor's lifespan, well not by that much from what we can tell at this point. Intel's guidance continues to be not setting VCore past 1.55V, VDimm past 1.65V and VQPI (uncore to us) past 1.315V when overclocking."

Hope this helps.

"Toss more threads at the i7 and the performance boost jumps to 34%, once again the i7-920 is faster than the QX9770."

"That's another 30%+ advantage for Nehalem. If you do a lot of 3D rendering on your system, Intel is going to give you $1400 worth of performance for $284. Merry Christmas."

- Source

The i7 920 easily reaches 3.5ghz OC'ed. They suspect they can get it to 4ghz stable, but you must note, running at such high voltages is STRONGLY DISCOURAGED BY INTEL AS IT WILL REDUCE THE LIFE OF YOUR i7 GREATLY. I think it's hardly worth the trade-off to attempt to break past VDimm's 1.65V recommended limit. You would need a very, very good watercooling setup to even attempt to do so...

So for all of you trying to push the i7 920 past 4ghz, you can expect that it is going to backfire eventually...

[NOTE TO GAMERS: "Overall in gaming tests the situations where Nehalem was faster than Penryn outnumbered those where it didn't, but upgrading to Nehalem for faster gaming performance doesn't make sense. We were entirely too GPU bound in all of these titles, if you want Nehalem it should be because of its performance elsewhere."- source]

However, if you don't have a recent investment, then it might be worth investing in Nehalem...

"The Core i7's general purpose performance is solid, you're looking at a 5 - 10% increase in general application performance at the same clock speeds as Penryn. Where Nehalem really succeeds however is in anything involving video encoding or 3D rendering, the performance gains there are easily in the 20 - 40% range. Part of the performance boost here is due to Hyper Threading, but the on-die memory controller and architectural tweaks are just as responsible for driving Intel's performance through the roof."

"Gaming performance is actually better than expected for Nehalem there were enough cases where the new architecture pulled ahead despite its very small L2 cache that I wouldn't mind recommending it for gamers. In most GPU limited situations however you won't see any performance improvement, at least with today's GPUs, over Penryn."

"There's no denying that the Core i7 is the fastest thing to close out 2008, but you may find that it's not the most efficient use of money. The first X58 motherboards aren't going to be cheap and you're stuck using more expensive DDR3 memory. If you're running applications where Nehalem shines (e.g. video encoding, 3D rendering) then the ticket price is likely worth it, if you're not then the ~10% general performance improvement won't make financial sense."


***Price comparisons

i7 920 Total: £759.43

Motherboard: Asus P6T Deluxe £252.81
CPU: Intel i7 920 £236.37
RAM: 6GB Corsair Dominator PC3-12800 (1600) £270.25

Core 2 Duo E8400 Total: £379.87
Motherboard: Asus P5Q Deluxe £150.93
CPU: E8400 £138.64
RAM: 4GB Corsair Dominator PC2-8500 (1066) £90.30

Core 2 Quad Total: £511.46
Motherboard: Asus P5Q Deluxe £150.93
CPU: Q9550 £270.23
RAM: 4GB Corsair Dominator PC2-8500 (1066) £90.30

***The hardware selected for the i7 build is top-quality (subtract ~£150 if you purchase lower-end mobo/ram)... The hardware selected for the Duo and Quad's were mostly mid-range (add ~£150 if you purchase higher-end mobo/ram... add as much as £600 if you purchase QX series...)

[kalniel]

Vdroop is a good thing to a certain extent - it's there to protect against overvolt when the load disappears - with LLC you have to be careful not to overshoot.

[Hawker1986]

Well ive got no personal experience with an i7 but my friend has just got one a 920 with a gigabyte UD5 and at 3.6Ghz has gone up from 15000-19300 in 3dmark vantage (with 2x4870 + 4850). Which is quite the boost if you ask me. Hes still waiting for his waterblock attachments to carry on overclocking further.

Hawker