Overclock.net banner

General Information

CPU
i7-875K
Manufacturer: intel
Core Speed: 3.89 GHz
Bus Speed: 155.55MHz
Multiplier: 25x
Voltage: 1.296V
Idle Temperature: 29 Celsius
Load Temperature: 68-74 Celsius
Motherboard
ASUS P7P55D-E-PRO
GPU
EVGA GTX 670 FTW
Manufacturer: nvidia
Memory: 2 GBytes
Core / Graphics Clock: 1267 MHz
Memory Clock: 6840 MHz
RAM
Crucial Ballistix Tactical
Size: 8 GBytes
Voltage: 1.5V
Frequency: 1600MHz
Hard Drive
Western Digital Caviar Black
Capacity: 1 TBytes
Crucial M500 SSD
Capacity: 960 GBytes
Optical Drive
LG Blu-ray Combo Drive
Operating System
Windows 7 Home Premium 64bit
Monitor
Samsung 2443
Keyboard
Rosewill RK-9000BR
Mouse
SteelSeries Sensei [RAW]
Audio
Sennheiser PX100 headphones
AntLion ModMic v4
Case
Silverstone Kublai
Cooling
Asetek 550LC
Noiseblocker Multiframe M12-P
Silverstone Case Fans
Power Supply
Silverstone Strider Plus 750
Just a PC that I can play games on and do all the usual home computer stuff with too. Bought this system from Falcon NW in 2010, its a Talon, and have done a couple of upgrades since then (gpu, mem, fans, overclock).

Rig Information

Rig Type
Gaming
Ownership Status
Previously Owned

Gallery

Comments

·
Registered
Joined
·
2,660 Posts
I think I have more room to go up in speed on the CPU but haven't felt the need to do it yet.
 
Last edited by a moderator:

·
Registered
Joined
·
2,660 Posts
For grins, I just tried to bump up the boost multi by 1, leaving everything else the same, that puts the CPU at 3.89. System booted and windows started up just fine, so I fired up a wPrime95 torture test with my temp monitoring tools running. Temps looked fine, high 60s with one core touching 70, pretty much the same as the do at 3.73. But 25 minutes in... BSOD 0x124 WHEA_UNCORRECTABLE_ERROR.So I guess if I really want to go higher, I'll need to play with voltage levels. I haven't really done that before. The builder I got this from had dialed in an OC that put me at 3.4 with 1.27v. I've upped the boost multis from there to get it to 3.73. But looks like thats as far as I can go w/o fiddling other settings.I'll do some reading here to get an idea of how large or small of increments I should work with, and what size of impact that may have on temps. I guess I'll start with just upping voltage and measuring temps w/o changing clocks to get a sense of the latter.
 
Last edited by a moderator:

·
Registered
Joined
·
2,660 Posts
This guide looks very helpful for me: same mobo, cpu, and simlar enough ram specs.http://www.masterslair.com/how-to-overclock-intel-core-i7-i5-i3-cpu-overclocking-guide
 
Last edited by a moderator:

·
Registered
Joined
·
2,660 Posts
I bumped it up a little more, to 3.89GHz @ 1.3v, kept notes about doing so here...http://www.overclock.net/t/1368807/overclocking-an-i7-875k-on-an-asus-p7p55-d-e-pro
 
Last edited by a moderator:

·
Registered
Joined
·
2,660 Posts
It's working fine at 3.89, but I might bring the voltage and clock back down to 1.27v and 3.73. Feels like I had to raise the voltage too much to make that small 155MHz step up in clock speed. I read an old article (dont have link) about the overclocking 875k that mentioned as clocks went above 3.8, power and temps started to go up less linearly wrt clock increases. Looks like mine does, so I might bring it back down to where its better behaved. Idk.
 
Last edited by a moderator:

·
Registered
Joined
·
2,660 Posts
I was able to bring vcore down two notches in the bios and its still stable at 3.89g. The manually entered value is 1.28125v and the actual value according to cpuz ranges from 1.288 at idle to 1.304 under load. Temps are a couple degrees cooler. So I'm going with this as an everday/always overclock.
 
Last edited by a moderator:

·
Registered
Joined
·
2,660 Posts
Found a really easy way to get a slightly cooler running system with my case. There are two intake fans mounted on the front of the case. The bottom/front fan has an unobstructed shot towards the horizontally mounted graphics card at the back. The top fan sits in front of the drive cage. I only have one drive, but I had a bunch of empty plastic shelves in the cage. I've slid those empty shelves out and the top/front fan now has a more clear shot over the mobo and at the exhaust fan on the radiator at the back. That simple change netted a few degrees in cooling. Everything else being equal, cooler is better
 
Last edited by a moderator:

·
Registered
Joined
·
2,660 Posts
It's getting warmer out (and in) with summer approaching. Taking a stab at lowering vcore another notch to 1.275 manual value which results in a max actual value under load of 1.296. Prime95 has been at it for ~35 minutes and so far so good. I'll let it run for 25 more minutes and claim victory if it doesn't blow up.
 
Last edited by a moderator:

·
Registered
Joined
·
2,660 Posts
Been so hot here recently and I have no AC. Swapped one of my 1350rpm front intake fans out for a 1600rpm slipstream, the lower one that lines up with the GPU. Makes a difference. I'll swap it back when the weather cools down again.
 
Last edited by a moderator:

·
Registered
Joined
·
2,660 Posts
Finally put my more quiet silverstone case fan back in... ah... the sound of peaceful silence again
 
Last edited by a moderator:

·
Registered
Joined
·
2,660 Posts
After 3+ years, the asetek started making a noise upon cold start, the noise would go away after a minute or so. Resolved that problem by flipping the radiator around such that the tubes are at the bottom instead of the top (the photo shows it before flipped it). Some air creeping in the closed loop. Hope the things last long enough for me to turn my make believe build into a real build
 
Last edited by a moderator:

·
Registered
Joined
·
2,660 Posts
Turns out it was a noiseblocker multiframe fan that was the real culprit with that odd noise upon cold start. Flipping the rad just moved the fan hub and made it better for a while. The noise eventually came back and it was the fan. As long as the hub is pushed fully in, no noise.
 
Last edited by a moderator:

·
Registered
Joined
·
2,660 Posts
Bumped it up to a round 4Ghz by moving the BCLK from 155 to 60Mhz and leaving the boost multiplier at 25x. I also disabled cpu spread spectrum and enabled xtreme phase full power mode on my asus p55d mobo, and bump Vcore up a notch, at idle it sits at 1.296v and under full prime95 load its 1.312v. Passmark cpu score went from 7038 to 7299 as a result.
 
Last edited by a moderator:

·
Registered
Joined
·
2,660 Posts
Well 4Ghz was not stable at 1.312v. I worked my way down from 160Mhz BCLK to find was was stable with that voltage. 156Mhz was where it landed. So the bump in voltage nets all of a 25Mhz bump in cpu speed (3.916Ghz). I'm definitely in the land of diminishing returns at this point.
 
Last edited by a moderator:

·
Registered
Joined
·
2,660 Posts
I've given this system to my friend's teenage kid now that Kickass-X99 is up and running.
 
Last edited by a moderator:
Top