I'm new to OC'ing and just built an i5-750 rig. I mostly use this PC for photo/video editing, web development, ms office work. Some DVD/video watching, very little hardcore gaming.
I'm looking for instructions / guidance on doing a mild overclock (mid 3 GHz) that should run stable for an always on PC. I haven't seen many i5 overclocking guides, especially for newbies who don't want to screw up the CPU/motherboard/RAM.
Intel Core i5-750
CM Hyper 212+ HSF
OCZ 4GB DDR3 PC3-12800, 9-9-9-24
Gigabyte Radeon HD 4670 1GB
Samsung Spinpoint F3 750GB HD753LJ
HP dvd 1260i
Corsair 400W CMPSU-400CX
CM Centurion 534 case
Windows 7 Pro 64-bit
Please read the Core i7 Overclocking Guide at the top of this Forum. Although it's not specifically for the i5, the architecture is nearly identical, and the principals are the same, so the Guide will still work for you.
Thanks, CompuTronix. I have read through that post before. I was looking for a little more specific instruction, perhaps with the i5 / ud2 motherboard combo and sample settings for a mild overclock. Like some ballpark settings where I might end up.
Another thing I'm not very comfortable with is the RAM timings. How do these come into play? They aren't mentioned in the guide.
I tried out a light overclock and seemed to do fine. I got the speed and timings on my RAM set first, then took the base clock up to 160.
So I ended up with 3.2GHz and 1600MHz for the RAM using a VCore of 1.25V and the DRAM at 1.64V (the BIOS had no 1.65V option). Temps were in the 40's idle and never broke 60 during the benchmarks I ran.
But this is where I could still use some help. I used Sandra Lite and HyperPi to do some comparisons and SpeedFan to watch temps/fan speeds. I wasn't sure which programs were best for judging performance or stability.
Also, the system fan never got above 800rpm. May just be because temps were good, but some monitors seemed to think it was malfunctioning. I noticed that Sandra Lite did not even read the speed correctly.
I'd also like to hear some opinions on how a mid-3GHz overclock compares to stock with Turbo mode enabled. A single core turbo gets low 3GHz when it needs it. So maybe there's not enough benefit for the power, heat, noise of a mild overclock that runs all the time vs. a stock with Turbo. I did notice a big difference in noise / heat of the case between the two.
Prime95 Small FFT's is the standard for thermal benchmarking. Since saturation is typically reached in less than 7 to 8 minutes, a 10 minute test is adequate. Also, cross-check your Core temperatures with Real Temp.
I think that 3.6 GHz should be an easy OC for virtually all i5-750s assuming the user has a cooler a little better than the stock one (yours qualifies). I'm not sure what your fan setup is on that case, but you should be thermally OK for 3.6 without any worries as long as it has reasonable airflow.
Obviously you should read the guide, but the very first thing I would do is disable the TurboBoost... that would definitely simplify any OC'n efforts by having your speeds locked in to what you specify.
I personally would turn turbo off and aim for 3.6ghz with no voltage increase. If you haven't done so, the "must have" test is prime95. If you can run that for 24 hours without a failure on any of your 4 cores you should consider yourself pretty stable...
And coretemp is what you should use for CPU temps.
As for the rest, gotta do your homework. The threads will tell you more than I can
I never run anything I own over 65°C. Thats a relatively "safe" overclocking temp.
If you are getting over mid 70° you are really asking for it in long term use in my opinion. That gigabyte mobo should be able to hold its ground though !
I'm also new to this but have exactly the same setup (board and CPU) except i'm on stock cooling. These are my experiences, just FYI because i dont really know much, this is my first oc:
1. Read all the stickies re temps and i7 oc a few times, they are very helpful. I used speedfan, coretemp and CPUZ to monitor things.
2. Voltages set in BIOS and reported CPUZ can differ by a lot, so 1.4 in BIOS is more like 1.36 in CPUZ. I have BIOS F3.
3. I could not get the turbo to kick in unless using the 20x multiplier, (this is with turbo set to enabled) eg 200x13 stayed there no matter what (and generated a cr@pload of heat), 142x20 clocked up to 24x. I don't know if that can be unlocked?
4. Set clocks above 3.3 w/ turbo mode wouldn't boot into windows, or would BSOD in a few mins. So definitely disable it and while your there disable all the C states until you have a stable oc.
5. 3.3 w turbo mode was unstable on one core because it was attempting to x24, and i wasn't willing to test higher Vcores.
6. A base clock of 200Mhz requires siginificantly more Vcore than i wanted to use >1.4
7. Intelburntest seems to get thrown by C states and the turbo when enabled - stable when all off, fails quickly when on.
I got mine stable at 3.6 (180x20), although getting there was hairy, things got rather hot rather quickly (posted in another thread)...mostly because i wasn't keeping an eye on temps when i should have been. Vcc is in BIOS at 1.285 (CPUZ 1.262 idle), Vtt 1.15, Vdram 1.64. Temps with C states enabled: 4 core load ~70C, 1 core load ~45, idle at 28-32. P95 6hrs stable. Not convinced i need that much speed at the moment so i may reduce back to 3.3 or 2.8 w/ turbo in the interests of longievity, however i'll save the profile in the BIOS.
As a side note, at stock auto everything, optimized defaults in BIOS the CPU failed Intelburntest's standard run in 3 flops.... All it took to pass all inculding the max test was manually setting the Vc at 1.25, on AUTO BIOS settings CPUZ reported Vcc at 1.34 or something like that!
Totally agree with CompuTronix... on a cold morning I had my i5-750 idling (at stock speed) around 18-20 C (depending on which core you're measuring). Ambient temperature in my drafty cabin was lower than that obviously. While I'd love to get used to that sort of setup, the reality is that in the summer my computer would absolute nuke itself if I ran it near the limit during the winter months.
I also managed to overclock my i5-750 CPU on a Gigabyte mobo, keeping voltages and temps very low in the same time. The full review can be found here . Some problems I encountered and the full setup are explained there.