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i want to OC my cpu just enough not to bottleneck my vid card

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Oct 29, 2011
new to the whole OC scene but i think im well prepared as far as heat sinks and fans. i have an XFX 6990 vid card that is bottle necked cus of my CPU, or so iv been told.
i want to OC the CPU enough to fix that, but without phase changing, liquid if all possible, i do have the cooler master v8 heat sink, aluminum i know -.- need copper, for my CPU.
now i need to upgrade the cpu heat sink to copper but i cant find a really good one that doesn't knock off my ZM-RC 1000 ram cooler, had the corsair dominator triple fan but it sucked allot of *** and made way too much noise. any suggestions on a kick *** copper heat sink for the CPU
i also have the EVGA power boost that goes in the pci slot to prevent power loss to the GPU from the pci slots, not sure about any benefactors from it but it had good reviews, and it was like 4$.
my PSU is a Kingwin Mach 1 1000w, and yes it powers the whole system, im aware that i might need a second PSU for my 6990 so i can OC the CPU, preferred not to but whatever is the safest.
by the way money is no option you get out of your system what u put in. is what i believe.

now here is my systems current specs summerized:

MS Windows 7 64-bit SP1
Intel Core i7 Extreme 965 @ 3.20GHz
Bloomfield 45nm Technology
12.0 GB Triple-Channel DDR3 @ 674MHz (9-9-9-24)

Gigabyte Technology Co., Ltd. EX58-EXTREME (Socket 1366)

AMD Radeon HD 6990 (XFX Pine Group)
CrossFire Disabled no second card...yet: comp:

CPU specific specs: Intel Core i7 Extreme 965

Cores 4
Threads 8
Name Intel Core i7 Extreme 965
Code Name Bloomfield
Package Socket 1366 LGA
Technology 45nm
Specification Intel(R) Core(TM) i7 CPU 965 @ 3.20GHz
Family 6
Extended Family 6
Model A
Extended Model 1A
Stepping 4
Revision C0/C1
Instructions MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, Intel 64
Virtualization Supported, Enabled
Hyperthreading Supported, Enabled
Fan Speed 1268 RPM
Bus Speed 134.9 MHz
Rated Bus Speed 3237.0 MHz
Stock Core Speed 3200 MHz
Stock Bus Speed 133 MHz
L1 Data Cache Size 4 x 32 KBytes
L1 Instructions Cache Size 4 x 32 KBytes
L2 Unified Cache Size 4 x 256 KBytes
L3 Unified Cache Size 8192 KBytes

RAM specific specs:Corsair TR3X6G1333C9 XMS3 PC3-10666 1333MHz 240-Pin DDR3

Memory slots
Total memory slots 6
Used memory slots 6

Type DDR3
Size 12288 MBytes
Channels # Triple
DRAM Frequency 674.4 MHz
CAS# Latency (CL) 9 clocks
RAS# to CAS# Delay (tRCD) 9 clocks
RAS# Precharge (tRP) 9 clocks
Cycle Time (tRAS) 24 clocks
Command Rate (CR) 2T

Physical Memory
Memory Usage 51 %
Total Physical 12 GB
Available Physical 5.79 GB
Total Virtual 24 GB
Available Virtual 17 GB
Number Of SPD Modules 6

now i am aware that upgrading my RAM to the fast 24gig would be nice but 12 does what i need it to do for now, cooling to me is more important lol,
unless it would help with the bottleneck issue sigh*
"The bottleneck issue" that you are concerned about is overblown. You should not be too concerned about it as it will only affect some games, and even if you could run your CPU at 6GHz (which you can't), in some situations, the bottleneck would still exist.

That is not to say I don't recommend overclocking your rig...I do! But you'r unlikely to notice much difference in most situations ;) Also, 12GB is just fine :thup:

Also, :welcome: to OCForums :)
^ I somewhat agree with this.

However since op is running a 6990 I would suggest an overclock of about 3.9-4gHz which is pretty mild for a 965(easily doable with ~1.3-1.35v).

Also that 1000w psu is more than enough for your setup.
Thank you very much MIAHALLEN, so as far as the bottleneck issue it squished unless i change my rig over to 2nd gen i7 blah blah, what about OC the CPU i would like a few percs, for example a simple game like SC2 uses 24-30% of my CPU its not that demanding of a game but that may also be some issues on my end lol. with current setup, and an educated guess, what do you think i would be able to achieve for my little 965
pwnmachine tyty on the input, but is it enough if im using the 6990 factory OC which is basically what the GPU was designed for lol and i will be adding a second 6990 to my rig in about a month, AMD recomends at least 1200 for optimal performance when crossfired, also opinion on coolermaster v8 heat sink, i sustain an overall average of 40 idle with background programs, and aroun 55 while running a game like aion, rift, or even crysis. suggestions?
^^ Oh I did not realize you were adding another 6990, in that case 1200w is a safe place to be. Also fwiw ati cards have a sweet spot with crossfire where 3 cards tend to scale better, have you thought of just adding another 6950/6970?
no i was not aware of that, i always thought the more the merryer lol, and no not really i was testing out the whole dual GPU setup and being you can only crossfire 2 6990 i was going to play lol but if i were id say 2x 6970 just because its the card i had before 6990
Dual 6990s is like 4-way Crossfire. And the fourth card is just HORRIBLE scailing, you basically get no performance boost past three. A better option would be to do what pwnmachine suggested, and you might be able to run it on your current PSU. 6990+6970.

You're not really bottlenecked that much, if at all. But a 4GHz OC should be pretty doable with high end air cooling. :)
Check the link in my sig for a good OCing guide. You should easily be able to get it into the 3.8-4.2GHz range :thup:
thanks guys imma play with the OC to the 3.8 and try to get 4.0+ with current setup, but im sure ill need a copper heat sink to get to 4 or higher. and as for the vid cards thanks for the input ill definately put my old card back in with the 6990 and check the marks but thatll be when i compare to the second 6990, im not saying you guys are wrong at all i just have my own curiosity to satisfy lol. ill be getting on my laptop to keep yall posted.
and again thanks pwn and miahallen for the info and u 2 knufire for the info on the cards thanks
Copper? Most coolers just have a copper base, there aren't that many FULL copper heatsinks out there, all I know of is the TRUE Copper (which was insanely heavy) and the revised Promilatech (sp?) heatsink, but it only had a few copper fins. Both didn't perform much better then their aluminum counterparts. The V8 should be fine for you, there are better performing heatsinks, but only by a few degrees, and they're all massive.

If you're sure you want to upgrade your heatsink, I'd actually go with a Corsair H80, zero worries about your RAM problems.
If you still have both of your 6970s...you can put them both in, you do have 3 x16 PCIe slots after all. That would be the same as adding a second 6990. Just a thought ;)
If you still have both of your 6970s...you can put them both in, you do have 3 x16 PCIe slots after all. That would be the same as adding a second 6990. Just a thought ;)

Or even slightly better since the 6970 is clocked a bit (50MHz) higher then the 6990. :thup:
well knufire i figured after 2yrs there would be much better heat sinks but guess not lol and as for and i have the corsair H70 or something like that its the one under the 80 and my cooling was actually better with the V8 than the liquid lol i was shocked and pissed that i just droped 70$ for liquid and my sink was better lol but i saved it for another rig, incase i get a little too nuts with this one. and miahallen thnx for the guide, no offence, i was expecting some half as **** that would cause me to blow my psu lol but im impressed at the simplicity of the guide. thanks again
ok im stumped now and confused at why it would be doing this:

CPU clock ratio- 15x
BCLK- last stable 170mhz
Vtt\Qpi- 1.215v
IOH- 1.140

now i have been jumping by 5 instead of 10 mhz on my BCLK because im a scardy cat and i dont wanna fry my CPU lol, anyways iv been passing stability test on a roll so when i went to 175 no boot. ok i might just entered one of those bclk holes so i up it to 180 again no boot, same train of thought increase it to 185. long story short from 175-200 no boot so i go back to 170, the stable one and run a stress test and what do you know...blue screen of death 10 seconds into stress test so i say great, go to 165 boots run stress crash, this process continued till i returned to factory settings which are now

CPU clock ratio 24x
BCLK- 133
QPI/Vtt- 1.175v
IOH- 1.175v

plz tell me its something simple that i am overlooking, everything was going great till now. mind you i followd that guide miahallen to the letter or i should say the decimal point, cuz GIGABYTE is good like that lol

oh and if your wondering factory settings of course run test with flying colors games work hole 9 yards
You need more vcore for that OC, what CPU heatsink are you using? Are you monitoring temps?
oh and blu screen said something like winodows detected errors so we shut down the computer to save stuff, and we are not going to tell you those errors we are just going to give you a bunch of letters and numbers to tell u whats wrong. good luck windows user

lol but im sure it was from instability. right?
Each chip is different in its ability, I suggest giving it a bit more vcore(0.01v increments).