Orthos - CPU Tests fine - Memory not

[AcxiDenTe]

Just like the title says.. I've overclocked my e6850 to 3.6GHz @ 1.3875Vcore, and if I run Orthos testing just the CPU.. it doesn't get any errors. However, I have Corsair pc2-6400 ram with 4-4-4-12 timings. I have to manually set my settings to 4-4-4-12 because my mobo thinks the ram is 5-5-5-15. but other than that, i have my ram running at 800MHz, which is 1:1 - FSB:RAM.. When I test with Orthos again, whether it tests the ram, or both ram and cpu, it fails, usually in less than a minute. I've tried bumping the ram voltage up to 2.2, to no avail, and I don't think i should have to loosen the timings since its just set to what the ram is rated at. BTW, I'm on an asus p5k mobo.. ram is sitting in the black slots as i've heard they're a little more stable for overclocking. so any ideas?

[DMB2000uk]

How much VCore?!?!? 3.875Vcore is insane.

Read it from the BIOS please

Depending on your cooling I would be hesitant at running it above ~1.40 for air, and ~1.5 for water for 24/7 use.

Add more voltage to the MCH/Northbridge to get your RAM running stable. The RAM voltage should be fine at stock.

Run memtest86+ from a CD and loop it on test 5 to see if your MCH is stable. The program will either crash or error if it needs more voltage.

Dan

[AcxiDenTe]

1.3875 or whatever it was.. is read directly from the BIOS.. Vdroop.. I can't remember what it is off the top of my head.. if i bump it to 3.7GHz, i gotta up vcore to 1.45.. and air cooling is doing fine. using coretemp.. under full loads, i reach about 60 degrees, at 3.7.. and only 50 for 3.6.. usually running about 30 at idle. are you saying i shouldn't need that much voltage to sustain 3.6GHz? i read this forum and it seems to be about right.

i agree that the memory should be fine at stock.. but its not for some reason that i've yet to discover. i've run through 2 loops of memtest86+ but yet to find anything there.

i'll consider adding more voltage for my NB, tho i'd prefer not to.

work in progress, i'm gonna see if i have to lax the timings at all, see if that fixes it, though i'd really like to not have to adjust those.

thanks for the help so far.

[DMB2000uk]

How long were you testing the ORTHOS CPU test originally for stability?

1.3875 is a safe amount, and will be fine for 24/7 use. (you did notice that you omitted the "1." and wrote "3." the first time you said it? )

Looks like you've made the best choice regarding where to leave the clocks, 3.6 should be sound (if you can get the memory working).

At 400Mhz FSB, i'm still putting my money on it being the northbridge needing more voltage. Of course that is provided that the memory is error free at stock settings.

Were you testing memtest with just test 5 or the whole shebang? Test 5 puts a bigger load on the northbridge so would find out if that is the problem quicker.

Dan

[AcxiDenTe]

lol, no i didn't notice that, i fixed that post now.. this morning i put the northbridge voltage at 1.4.. i honestly can't find what normal voltage is for that, and what the max limit is, but regardless, it didn't help any, so it might have to go higher. i've also got my memory set to 2.2 vdimm atm, and that didn't help either.

and currently i left my computer running a prime95 version 25.5 test for just the cpu.. its the version that'll test both cores, i just wanna make sure its still working alright. when i get home i'll run memtest over night, but am not really expecting any errors there either... but who knows.. so do you know what normal/max voltages for the northbus are? thanks for the help again.

[largon]

You might want to try this prog, it's a very intensive Windows based RAM stress tester:
http://hcidesign.com/memtest/

Make sure you run 2 instances of it with ~equal amount of RAM assigned for each.

[kenc51]

What motherboard are you using?

[AcxiDenTe]

K, i'll look into that program. I'm using an Asus P5K mobo.. i ran memtest86+ overnight last night, and had three errors throughout it. I'd already slowed my timings to 5-5-5-15.. 1.4vcore right now.. 1.55 NB voltage.. so i have no idea, i'm running orthos again right now, should go for a long time.. we'll see..

[AcxiDenTe]

OK, I"m starting to wonder if there is something wrong with my RAM.. after many unsuccessful configurations, i gave up and set everything back to stock.. my mobo still keeps my RAM at 5-5-5-15 for some stupid reason, but i left it there anyways.. I still can't get more than 3 minutes into orthos RAM test before it fails.. should i get it replaced? or could something else be the problem still?

[dicecca112]

You might want to try this prog, it's a very intensive Windows based RAM stress tester:
http://hcidesign.com/memtest/

Make sure you run 2 instances of it with ~equal amount of RAM assigned for each.

In OS ram testers are terrible, the miss a lot. In the absense of a stand alone test card like Nate (Apoptosis) uses in his Memory reviews, MemTest is the next best thing

[AcxiDenTe]

after running memtest overnight on each module individually, one of my modules had no errors, and one had 28 errors through 40 passes.. so I guess i'll work on getting both modules replaced since they were manufactured as a pair.

[werty316]

Great to hear you found that one stick was bad which obviously was the problem if Orthos gave you ram errors.

[kenc51]

Make sure you are using the BLACK RAM slots
You could also try to loosen the timings a tad, the P5K uses tight timings when set to auto. Also, when you set the memory voltage to AUTO, it only supplies 1.85v, try upping this to 2.0v