I am new to the world of Overclocking. I have a setup that I'm fairly certain will handle it well, but I don't want to chance burning up my CPU. I have an E8400 3.0 GHZ dual core processor with stock Intel fan (which I would like to OC to 4.0), an EVGA 790i Ultra SLI motherboard, 4 GB of 1800 MHZ DDR3 OCZ Ram (Nvidia certified), and an EVGA GTX 275 1792MB DDR3 video card. What would be the best method to OC my system without getting my voltage and temperature into the unsafe range? Thanks in advance!
To Start, i don't think that overclocking that E8400 to 4.0 would be a good idea on the Intel Stock cooler, those things are not suited for medium-high to high overclocks. I would say that the safest bet would be to go to 3.6 with stock Intel cooler. As treefrog said, use that guide for overclocking, it is a great guide that has helped out many-a-overclock.
I used the guide mentioned above, and get a lot of good information reguarding overclocking. I was able to oc the processor to 4.1 ghz, wihout going over 60 degrees Celcius (according to Realtemp). I changed the FSB speed of the CPU to 1800 Mhz (enough to match my ram speed), then slightly decreased the CPU core voltage. I ram the computer for a while without any difficulty, but when I tried to run Crysis, it crashed to a blue screen twice in a row. (I am using Windows 7 Home Prem. 64 bit.) It then did the same thing with Far Cry 2. I wasn't sure what the problem was, so I set the BIOS back to normal, and it resumed perfect operation. Could this be an issue with the Core Voltage being to low? If not, what could I be doing wrong?
It sounds like like you may need to bump up the voltage a little to gain stability. You should download and install Prime95 (there are 2 versions: one for Winx86 OSes and one for Winx64 OSes). Run Prime 95 for several hours, maybe overnight - when it is able to run that long at your OCed settings, you ought to be able to play your games.
Your wasting your time going for 4ghz clocks with an E8400.
The numbers wont add up to real world performance and you will be pushing maximum safe vcore levels to get it there (1.320v's) You will not achieve this vcore on a stock cooler regardless.
The problem isnt the cpu its your mobo chipset, it runs out of steam over 1600fsb.
While you will get your 4ghz in benchmarking, the difference with it at say 3.6ghz will be very small. In actual fact in real world performance I found my game performance actually dropped off noticably with lagging and artifacting a common problem at the higher clocks. Stuttering was also another byproduct of an overworked fsb.
You will get people crap on saying there chip gets to 4.2 and flies like a racehorse on crack, but there just numbers. What you want is real world usable performance.
The sweet spot for a E8400 is 3.6ghz, ive tweeked mine up and down the speed range for years and always find this to be the allround sweetspot.
Follow these steps and give it a go.
1. Set your frontside bus to 1600mhz(maybe 400 in your bios due to quad pumping)
2.Set your Vcore manually to 1.265v's. Never OC on an Auto vcore setting especially with a stock cooler, most mobos get rather volt happy on auto.
3.Try to set your ram to a 1 to 1 fsb divider, this will entail 1200mhz and may be out of spec for your ddr3, I have consistently found that running your ram at a 1 to 1 ratio provides more performance with the lga775 package than running unlinked at higher speeds on your memory. The upside to the lower speed is that you should be able to lower your ram timings as well.
4. Reboot and confirm your settings with CPUz. Confirm your FSB speed, FSB divider and Vcore. It is not unusual for your vcore to be out with what you set in bios. Aim for 1.265v's in CPUz, this may entail raising or lowering in your bios. Your FSB divider ratio will be displayed under the memory tab of CPUz.
5. While running a temperature monitoring utility in the background run prime 95 for 30 mins and confirm temps. 50-60 degrees under full load after 10 mins is satisfactory. If higher than 60 you can drop vcore at 0.01 increments. Reallistically you should be able to hit 3.6 right down to 1.24v's if you have a decent chip.
(mines had a hard life and needs more juice these days)
Saying this if your temps are sitting around the mid 50's under load at 1.265v's I would be inclined to just leave it alone.