My first i7 920 OC - a few noob questions...

[derdeb]

Hey,

I've been trying to learn all this OC stuff (brand new to it) for the last couple of days, and I think I have a pretty good grip on it. I posted some questions in another forum, but I haven't really gotten a straight answer.

I thought I would try this community to see if anybody could help.

Firstly, my specs:

Intel Core i7 920
Intel DX58SO Motherboard
BFG nVidia GTX 275 OCX
GSkill 6GB 1600MHZ DDR3 RAM (9-9-9-24)
TRUE 120 Black Edition +2 S-Flex Push/Pull
Corsair HX750 PS
NZXT LX Sentry Fan Controller

So far, I've overclocked my cpu to 3.7GhZ at 185 Mhz x 20. I've lowered the QPI to it's lowest and have disabled the turbo and speedstep features.

I've also manually set my CPU voltage to 1.2 instead of dynamic. My other voltages remain at stock. My memory is currently at 6x running at 1080 Mhz on 1.5 volts.

I can run intelburntest on high for about 20 minutes on 8 cores hitting a max temp of 65 degrees. My average idle across all cores is about 37 degrees.

Now, here's my question.

Firstly, whenever I try to increase my memory multiplier to 8x, I can't post. No matter how much voltage I give my CPU (max I gave it was 1.3) or how much voltage I give my memory (max I gave it was 1.6 - the rated max).

Is this normal?

Secondly, should I be worrying about my memory timings. I've attached a screenshot of my current CPU-Z memory and CPU settings. Currently, they're at 8x8x8x19. My RAM is rated at 9x9x9x24, so I guess my current latency is better. Should I refine it more?

Thirdly, should I now be increasing my uncore multiplier as well? Currently, it's at x17.

Any help is appreciated.

Cheers.

 

[MIAHALLEN]

First off... to OCF

Check out my overclocking guide here:
http://www.overclockers.com/3-step-guide-overclock-core-i3-i5-i7/

I've also manually set my CPU voltage to 1.2 instead of dynamic. My other voltages remain at stock. My memory is currently at 6x running at 1080 Mhz on 1.5 volts.

Great OC at only 1.2V

Firstly, whenever I try to increase my memory multiplier to 8x, I can't post. No matter how much voltage I give my CPU (max I gave it was 1.3) or how much voltage I give my memory (max I gave it was 1.6 - the rated max).

Is this normal?

Very normal. Since most of your voltages are still stock.
Sounds like the memory controller is the limit here, the VTT voltage powers the memory controller, and it needs more voltage to run the memory faster

Secondly, should I be worrying about my memory timings. I've attached a screenshot of my current CPU-Z memory and CPU settings. Currently, they're at 8x8x8x19. My RAM is rated at 9x9x9x24, so I guess my current latency is better. Should I refine it more?

Wait on the memory until you get your bclock up to speed (in the guide)

Thirdly, should I now be increasing my uncore multiplier as well? Currently, it's at x17.

Yes, but this is less important, leave it on auto until later

 

[derdeb]

First off... to OCF

Check out my overclocking guide here:
http://www.overclockers.com/3-step-guide-overclock-core-i3-i5-i7/


Great OC at only 1.2V

Very normal. Since most of your voltages are still stock.
Sounds like the memory controller is the limit here, the VTT voltage powers the memory controller, and it needs more voltage to run the memory faster

Wait on the memory until you get your bclock up to speed (in the guide)

Yes, but this is less important, leave it on auto until later

Hey thanks for the reply.

I'm not sure I understand the theory of setting the Bclck multiplier down to a lower value first and increasing bclock. Won't leaving it at 20x and slowly increasing the bclock do the same thing?

Also, I can't find the CPU VTT setting (assuming it's different from the core voltage itself) for the life of me on my DX58SO. Is there another name for this?

 

[MIAHALLEN]

Well...bclock has it's own overclocking limit completely separate from the CPU limit...so if you don't know what either limit is, and you're overclocking both at the same time...you'll eventually reach the limit of either the bclock or the CPU, but you won't know which. If you do one at a time, you'll know the limitation of each

VTT is also referred to at QPI...check for that

 

[psionic98]

take the memory down to 9-9-9-24-auto-2t @ your factory volts to take the memory out of the mix (dont use XMP profiles if you dont have to)
set the memory ratio to like a 2:8 which should put it to like 1066 and gets it out of your way for overclocking the core.

then its just trial and error to see where you can sit stable at..i dont think at 1.2v you are going to see very big overclocks as even d0 cores need 1.25 or more to keep stable over 3.8GHz.. im resting at 3.8 @ 1.26v and very stable, Im still working on my memory.. but i also upped my VTT(QPI) to +150

 

[derdeb]

Well...bclock has it's own overclocking limit completely separate from the CPU limit...so if you don't know what either limit is, and you're overclocking both at the same time...you'll eventually reach the limit of either the bclock or the CPU, but you won't know which. If you do one at a time, you'll know the limitation of each

VTT is also referred to at QPI...check for that

Ah, QPI i have.

However, I'm still confused about this block/cpu business. Is there a difference in running a bclck of 200 x 18 versus a bclock of 175 x 20?

They both give an output of 3.6 Ghz. I was under the impression that the multiplier should always be at 20...

 

[kkpudge7]

However, I'm still confused about this block/cpu business. Is there a difference in running a bclck of 200 x 18 versus a bclock of 175 x 20?

They both give an output of 3.6 Ghz. I was under the impression that the multiplier should always be at 20...

Generally speaking a lower bclk and higher multi (175x20) will produce lower temperatures, but each chip reacts differently to these settings. The big picture is just finding where your particular chip is stable, read some of those links and keep learning, you will get the hang of it Also, do a search for the user Earhdog, he has some very useful links in his sig, might want to check those out as well.

On a side note, you were asking about the Uncore frequency earlier in the thread, this was the key to my overclock. Usually the rule of thumb is memory multi x2 = uncore (8x memory mulity would yeild a 16x uncore multi). In my case it is memory multi x 2 + 1. So for an 8x memory multiplier I run a 17x Uncore multilplier. I have seen on a number of situations where this stabalized an overclock. Worked for me, might want to check it out.

 

[derdeb]

Generally speaking a lower bclk and higher multi (175x20) will produce lower temperatures, but each chip reacts differently to these settings. The big picture is just finding where your particular chip is stable, read some of those links and keep learning, you will get the hang of it Also, do a search for the user Earhdog, he has some very useful links in his sig, might want to check those out as well.

On a side note, you were asking about the Uncore frequency earlier in the thread, this was the key to my overclock. Usually the rule of thumb is memory multi x2 = uncore (8x memory mulity would yeild a 16x uncore multi). In my case it is memory multi x 2 + 1. So for an 8x memory multiplier I run a 17x Uncore multilplier. I have seen on a number of situations where this stabalized an overclock. Worked for me, might want to check it out.

Hey,

Yeah, I've set my uncore multi to double plus one of my mem multi. I managed to get my system on a pretty stable OC (intelburntest high stress test) at 3.8GhZ.

My settings are:

190 Mhz x 20
core voltage of 2.2
temps max out at 67 under load high 30's at idle

memory is at a 6x multiplier DRAM frequencey of 571MhZ 8x8x8x19.

One thing I noticed was my QPI voltages aren't in .02+ increments...so I'm not sure how to properly set that.

Should I focus on getting the memory up to a 8x or is it good at 6?

 

[bda1967]

Ah, QPI i have.

However, I'm still confused about this block/cpu business. Is there a difference in running a bclck of 200 x 18 versus a bclock of 175 x 20?

They both give an output of 3.6 Ghz. I was under the impression that the multiplier should always be at 20...

The BCLCK affects everything (CPU, QPI, RAM, UNCORE) so the higher you set your BCLCK, the higher everything runs unless you lower the individual multipliers.

CPU Freq=Bclk x Mult.


Uncore Freq=Bclk x 2(Uncore Mult.) or BCLK X (2X+1)


Mem Freq=Bclk x Mem Mult (Usually a 2:8 ratio)


QPI Freq=Bclk x QPI Mult

Two examples of different BCLCK and Multiplier settings. Both will yield the same CPU frequency of 4000MHz (OK one is 3.99GHz) but will also give slightly different readings for the RAM, UNCORE and QPI though.


CPU= BCLK of 200 x Mult 20 = 4000 MHZ / BCLCK 190 x Mult. 21 = 3990 MHz

RAM=BCLCK of 200 x (8 Memory Mult.)= 1600 MHz / BCLCK 190 x (8 mem. mult)= 1520 MHz

Uncore= BCLCK 200 x 2(8 RAM mult.) = 3200 MHz / BCLCK 190 x 2(8 RAM mult.)= 3040 MHZ

QPI= BCLCK 200 x 36 Mult.= 7200 GT/s / BCLCK 190 x 36= 6840 GT/s

 

[bda1967]

Hey,

Yeah, I've set my uncore multi to double plus one of my mem multi. I managed to get my system on a pretty stable OC (intelburntest high stress test) at 3.8GhZ.

My settings are:

190 Mhz x 20
core voltage of 2.2
temps max out at 67 under load high 30's at idle

memory is at a 6x multiplier DRAM frequencey of 571MhZ 8x8x8x19.

One thing I noticed was my QPI voltages aren't in .02+ increments...so I'm not sure how to properly set that.

Should I focus on getting the memory up to a 8x or is it good at 6?

You will want your RAM to run at it's rated speed of 1600MHz (or close to it) so you will need to use the 8 multiplier. 190 x 8 = 1520 MHz.

 

[Neuromancer]

Best practice for me on i7 was treat it like an AMD


Clcok your memory, find what speeds, timinigs voltages it needs

Work on max bclk and associated settings


only then worry about cpu speed

After time spent learning the arch, I managed to max out my E758 board (222 BCLK) on air. (I got a lemon that hit the hardwall )

 

[derdeb]

You will want your RAM to run at it's rated speed of 1600MHz (or close to it) so you will need to use the 8 multiplier. 190 x 8 = 1520 MHz.

Everytime I try to raise my mem multiplier from 6 to 8, I can't post.

I've tried everything from increasing my Core voltage to 1.3, increasing my QPI to 1.3, increasing my IOH to 1.3 and increasing my mem voltage to 1.56.

Is it better to half a higher blck and a lower mem multiplier or the otherway around?

Also, just to confirm, my current 6x multipler memory is faster than what I had it at stock...right?

 

[bda1967]

Take DRAM voltage to 1.65v. EDIT: Yes your current 1142MHz is faster than the stock 1066MHz but your RAM is still underclocked.

 

[derdeb]

Take DRAM voltage to 1.65v. EDIT: Yes your current 1142MHz is faster than the stock 1066MHz but your RAM is still underclocked.

My memory is rated for a max of 1.6 volts - which I've set to, and I still can't get it to post at an 8x multiplier...

 

[bda1967]

Have you run Memtest86 on your RAM yet? After you verify that all of your RAM is good, set DRAM voltage to 1.65v, QPI to 1.4v, QPI PLL to 1.2v and your RAM settings to 9-9-9-24-1T. If 1T does not work try 2T.

 

[derdeb]

Have you run Memtest86 on your RAM yet? After you verify that all of your RAM is good, set DRAM voltage to 1.65v, QPI to 1.4v, QPI PLL to 1.2v and your RAM settings to 9-9-9-24-1T. If 1T does not work try 2T.

Yeah, memtest ran fine. I don't know about setting my mem voltage past 1.6 though since it's max rating is only 1.6. I don't really feel like frying my RAM.