Originally Posted by stolid
Looking for some feedback on my overclock for an E5450 on a Gigabyte EP45-UD3L. It's currently at 424*9 = 3.81GHz at 1.275v in BIOS with 1:1 FSB:RAM and timings 5-5-5-15 (2x 2GB G.Skill DDR2-800 1.8v sticks at 1.9v). I got an error in prime when I tried FSB 434 (3.9GHz.) with all other settings the same.
Am I thermally limited yet? I'm not really sure whether to believe these temperatures or which program - what is the Tj max for these CPUs? Do you think it's necessary yet to mess with voltages other than vCore? Obviously, I don't want to increase any voltages if I'm at a thermal limit.
That's very tight memory timings so you will probably want to keep your memory at conservative speeds/timing until you dial in your max CPU overclock. Trying to O/C with tight memory timings and/or high memory speeds will preset a significantly higher challenge to O/C your CPU and reach stability especially with higher bus speeds. I would ONLY attempt to improve memory performance as the VERY LAST step in tweaking your overall system. You may need to go back and re-run that same test that failed but with your memory at more conservative settings (AUTO for memory, view the values chosen by AUTO and then manually set those same values
for memory to give you a good place to start). Run MEMTESTx86 from a bootable USB drive and verify your memory is stable as 1st step.
As far as messing with other voltages besides vCORE, absolutely
if you are looking to push your bus speed up (I don't know P45 specifically but I suspect this is true for all S775 chipsets with a north-bridge. I have to adjust just about every voltage in my system to reach my 4.65Ghz "24/7" O/C (this is a 1825Mhz bus). I could share what I use for BIOS settings but I have 790i chipset and will be different from your P45.
You indeed do not have much thermal headroom right now but that is probably not your limitation YET if you haven't messed with other voltages (however I think you are VERY close to your thermal limit). 80C is probably the most you'll want to get as a max temp under high stress (looks like you are on AIR) but 70's is better. I don't really think you are going to be able to go too much higher without a water block but I would suspect you could get closer to 4Ghz with some additional tweaking (you have a 9x multi and room to raise bus speed). According to Core temp the TjMax = 100C for both of our CPUs (I have X5470). I'm not going to test that limit and find out
but I can tell you that at least for me, 85C hasn't showed to be a "problem" it is just about as high as I'm willing to take my CPU. As a general rule of thumb I would say that 80C as your max is safer. That's a full 20C delta from TjMax