About 3 weeks ago I found my self with a new build searching the web for the quick OC fix like
everyone else and  to no avail I could find hardly anything that was worth a darn so I had to
sit back and view about 4 different forum  post just to get the right info to get in the ball park.
 
So I thought I would post what my results were in the hopes to help others!!!!
 
Rig:
I7 860
EVGA P55 FTW 200
6g GSKILL 2000Mhz
3 - EVGA 275 GTX's
Ultra 1200 watt X4
Swifttech GTZ Watercooled with a 3:120mm Rad
The OC:
4.0 Ghz
36 c Idle 68c Load
BCLK: 200
Multi: 20
Vcore: 1.35v
VTT: 1.35v
Ram: 1.60v (set to your rams specs)
PCH: 1.05v
PLL: 1.80v
PCIE: 104
QPI: 4.270 GT/s
MCH Strap: 1600 Mhz
CPU PWM Frequency : 849 Khz
VTT PWM Frequency: 634Khz
Hyper threading/ C1E support/ Speed step/ C-State : All Disabled
The Ram I set to my timmings and the just dropped the Mhz down to 1600 from the factory 200Mhz with a divider of 2:8
I then ran this with 25 passes of Intel Burn Test and 6+ Hours Of Prime 95
 
******Just a Little up date, if you guys wish to run with Hyperthreading turned on just bump the cpu volts up to 1.375 and the vtt up to 1.375 and your good to go!! ********
 

 
Here are Pics of my Bios settings:
 

 

 

 

The main Factor in this OC was the adjustment of the Vcore and VTT Frequency I had tried everything I could to get this stable but it just was taking an unreal amount of voltage(High Temps) until I changed the both of them the only thing I have seen them do is just cause your Voltage Regulators to run a little bit hotter but EVGA tech says 100c and under is ok.
 
I hope this info will help in your OC and remember everyones results my very b/c of cpu/motherboard differences.
 
GOOD LUCK AND HAPPY OCING!!!!
 
Pics of current rig:
 

 

 

Thanks for this - what about with HT on?

Only reason to hget a 860 over a 750 is HT after all......

evillman

@OC: Nice :D

@Setup:Man, your case is a mess. 
Rearrange all the cables from the source and this watercooler. :X

All cables have now been sleaved ( neon, the fan that was left I was in a slight rush spending a week on this teardown and rebuild)and the water cooler is sideways b/c that is way the 775 socket holes are lined up with this motherboard (it has both 775 and 1156)

man, your computer looks like a monster pc.

What BIOS version are you using?

Many thanks.  I have two GTX 275 video cards.  Do you see an improvement with three cards.  I should upgrade the BIOS since my temps are about 6 to 10 degrees hotter than yours (even with the Corsair H50).  I love to see temps for a I7 860 CPU with HT enabled.  Afterall, isn't that the reason why we purchased the 860 instead of the 750?

Thanks,

I noticed you painted the inside of your computer, what spray paint did you use?  Did you use some type of hardening agent afterwards?

Very good.  Thanks.  I was thinking about painting the outside red and the inside black.

By the way, I am using your overclocking profile, with the exception that I bumped up my DDR 3 to 2000.  When you tested your overclock did you ever use the high setting of Intel's Burn In test?  I am trying to get my system stable using pretty much the same profile as you, but a slightly faster RAM setting.  Any suggestion on what setting to bump up?
 
So far I bumped up the DDR PWN to 634 and the MCH to 1867, I am not sure if that will increase stability or just create unnecessary heat.

Thanks,

No problem glad I could help!

Thanks for the info I have been running my memory at 1600mhz I think I might try bumping it up and running at that !

Thanks!

No he can't use 3x16.. only 3x8, but there is no difference in high-resolutions..maybe in the future it could make a difference.

Can I use Twice ATI 5970 in Crossfire with EVGA P55 Classified 200 ?

Will I get FULL 16x SPEED PCI-e Lane on both ATI 5970 using the Nforce 200 Chipset that sitted on EVGA P55 Classified 200 Motherboard ?

Can I use Twice ATI 5970 in Crossfire with EVGA P55 Classified 200 ? Will I get FULL 16x SPEED PCI-e Lane on both ATI 5970 using the Nforce 200 Chipset that sitted on EVGA P55 Classified 200 Motherboard ?

andych

Can I use Twice ATI 5970 in Crossfire with EVGA P55 Classified 200 ?

Will I get FULL 16x SPEED PCI-e Lane on both ATI 5970 using the Nforce 200 Chipset that sitted on EVGA P55 Classified 200 Motherboard ?

no you won't get 2x 16 PCI Lanes directly to the CPU.
Only if you use Nvidia Cards, and only 2 of them, in slot 2 and 3  - then you've got 16/16, (you have to disable all other PCIe slots). 
But not really.. because the NF200 bundles the 2x16 to one signal, which is send to the CPU. 

NF200 is designed vor Nvidia Cards, not for ATI.
ATI will only work in 8/8/(8).
When you use 3 Nvidia Cards, it's never 16/16/16. Only 8/8/8.

For - 2x 5970 you shoud buy a X58 board. 

TKE395,

One last question. I was looking at the post above mine and it looks like two cards can run in PCIe slots at x16, but only in slots 2 and 3.  Can you confirm that?  If that is true, it would place the two GTX 275 cards directly on top of each other and increase the noise level considerably.  My question is can you use slot 1 and slot 3 instead of slots 2 and 3 and still maintain the full x16 bandwidth?

Thanks!

you should be able to use slots 1 &3 at 16x ......


No no - the first pcie Slot (not the 1x) is the one which is working with 16x directly to the CPU, without using the NF200 Chip.

if you put another graphicscard in Slot 2 or 3, the first slot decreases from 16x to 8x - everytime. Because..  the NF200 Chip needs a connection... when using slot 1 with 8x and slot 3 with 16x, then the first slot gets 8x to the cpu, the NF200 gets 8x to the cpu, and slot 3 gets 16x to the NF200 - NOT to the cpu.

Only if you are using slot 2 and 3, and don't use any other card in a pcie slot - and disabled all other slots by the jumper (except slot 1 1x) - then
slot 2 and 3 working with 16x/16x to the NF200 and the NF200 works with 16x(8x/8x) to the cpu.
When you using a soundcard like X-Fi in one PCIe slot (f.E.), then the NF200 only works with 16x/16x to the cards, and 8x to the CPU.  

When you use 3 graphic cards, then it is 8x/8x/8x to the NF200 and 8x to the cpu. 

The NF200 works the same way on x58, but the x58 allows 32x .. not only 16x, like the P55 chipset. 
Here an example from the P55 200 Classified   

   


Sorry.. my english is not that good, but I hope you understand me.. and how the NF200 works. 


If you don't understand me.. read this: http://www.hardwarecanucks.com/forum/hardware-canucks-reviews/27117-evga-p55-classified-200-lga1156-motherboard-review.html


and this: http://enthusiast.hardocp.com/article/2009/01/06/nf200_true_3way_sli_preliminary_results

and this: http://www.overclock.net/intel-motherboards/600896-what-nvidia-nf200.html

In my opinion, it's a mythos to have 16x - because you play on HD or higher, max settings and everything,.. so the card never needs 16x to the cpu...  maybe in the future, but at the moment, it's no problem to use "only" 8x/8x/8x or 16x/16x to NF200 .. with 8x/8x to the CPU.
You'll never feel a difference!