t0mz0r Posted June 6, 2009 Share Posted June 6, 2009 Hey boys Lately I've been testing a couple high-speed DDR3 kits, and at somewhat random - on a wide variety of X58 boards - one or more memory channels are disappearing, i.e. dropped from both BIOS and effective use. Has this happened to anyone else? At first I noticed this incorrect memory detection behaviour on an Asus Rampage II Extreme when using specific settings for CPU VTT (QPI/Uncore voltage) and memory speed, which led to one of the three channels being dropped, leaving a 3x2 GB kit to boot with only two of the three modules active. The issues were most apparent when using a low QPI/Uncore voltage or too tight timings - or at speeds in excess of 800 MHz (DDR3-1600), anything less ran without issues. It should be noted, that CPU-Z would display all installed 3x2 GB, but testing memory bandwidth reveals that only 4 (2x2 GB) is being used. I tested every possible aspect, even ran checked all modules with MemTest. The board was then RMA'ed, and the replacement board has so far not shown similar issues with +1866 MHz tri-channel kits. Initially I thought this to be a BIOS issue, but nowadays I'm also testing the W35xx series Xeon's which are doing just fine. No problems regardless of selected memory speed and/or tight timings. This got me thinking that loosing memory channels might be related to a partially degraded internal memory controller (IMC) on my old and used 965 ES. So, has anyone else had similar experiences with disappearing memory? And is the missing memory channel caused by the IMC or the need for a combo of ideal memory settings? (as well as finding the optimal QPI voltage of this particular sample) - Tom :ws: Quote Link to comment Share on other sites More sharing options...
Massman Posted June 6, 2009 Share Posted June 6, 2009 Had the same issue when benching the GBT X58-Extreme under cold: there was just no way to recover the third channel. Tested the same chip on a different board afterwards and the third channel was back, even under cold. Quote Link to comment Share on other sites More sharing options...
t0mz0r Posted June 6, 2009 Author Share Posted June 6, 2009 Had the same issue when benching the GBT X58-Extreme under cold: there was just no way to recover the third channel. Tested the same chip on a different board afterwards and the third channel was back, even under cold. Hmm, so far I've tried a few different things that seem to be working - however shortlived they may be: Total power down at reboot, not simply the normal restart of the system Complete board and BIOS shutdown (with battery removed) before trying again Removing one DIMM, setting easier timings, reboot and re-install missing DIMM Raising "vQPI" as well as manual input for Uncore Having a look at DIMM REF voltages at the moment to see if there's something in there affecting this issue. Quote Link to comment Share on other sites More sharing options...
K404 Posted June 8, 2009 Share Posted June 8, 2009 Damn! the thread was on here, not XS. I've posted something on XS, I believe its happening to me as well http://www.xtremesystems.org/forums/showthread.php?p=3835661#post3835661 Thanks Tom for the nudge is diagnosis. I was blaming lowgap Quote Link to comment Share on other sites More sharing options...
t0mz0r Posted June 8, 2009 Author Share Posted June 8, 2009 Damn! the thread was on here, not XS. I've posted something on XS, I believe its happening to me as well http://www.xtremesystems.org/forums/showthread.php?p=3835661#post3835661 Thanks Tom for the nudge is diagnosis. I was blaming lowgap np which processor are you having this issue with tho? Just wondering if its an old c0 like my one, which also does it.. Quote Link to comment Share on other sites More sharing options...
dinos22 Posted June 8, 2009 Share Posted June 8, 2009 i lost the first channel at GOOC comp last week and changed boards only to find it was the IMC that was damaged changed CPU as well all good at home i am having that issue right now and it's the RAM kit that's dead/about to die >> Corsair 2000GT Dominators cries in my experience it was faults with hardware unfortunately [edit] i remember junior having this issue with asus R2E but i was a board issue there....weird Quote Link to comment Share on other sites More sharing options...
t0mz0r Posted June 8, 2009 Author Share Posted June 8, 2009 at home i am having that issue right now and it's the RAM kit that's dead/about to die >> Corsair 2000GT Dominators cries in my experience it was faults with hardware unfortunately Almost same here, Corsair Dominator 1866c7's and OCZ Blade 2000c7's Hmm hope the kits arent about to die on me :( 1 Quote Link to comment Share on other sites More sharing options...
K404 Posted June 8, 2009 Share Posted June 8, 2009 Corsair Dom 3GB and Crucial Tracer 6GB (2 days old) 920 C0 CPU. At the mo I think its a sign of instability, not impending death... but im still fairly new to I7. Im typically running 1.44vQPI and either 1.65 or 1.75vDIMM. Quote Link to comment Share on other sites More sharing options...
t0mz0r Posted June 8, 2009 Author Share Posted June 8, 2009 mhmm, in terms of QPI voltage I use 1.450-1.475 for 24/7, a bit higher when cold my vDIMM is set at 1.65 for everyday usage, up to 1.75 when benchmarking (ram sticks are being properly cooled) Quote Link to comment Share on other sites More sharing options...
dinos22 Posted June 8, 2009 Share Posted June 8, 2009 i have a kingston kit which is fine i've also tortured my samsung based Corsair 1866 kit for ages also fine Quote Link to comment Share on other sites More sharing options...
t0mz0r Posted June 8, 2009 Author Share Posted June 8, 2009 you be thinking this is an Elpida Hyper issue? Quote Link to comment Share on other sites More sharing options...
K404 Posted June 8, 2009 Share Posted June 8, 2009 Neither of my kits are Elpida CAS 6 appears to be a fantasy. Quote Link to comment Share on other sites More sharing options...
russianhaxor Posted June 8, 2009 Share Posted June 8, 2009 I kind of do a lot of tech support on the i7 and in many instances the disappearing memory channels is either a result of a poorly seated processor or a failing IMC. But if it was working before and just went out i doubt its a physical movement. Quote Link to comment Share on other sites More sharing options...
t0mz0r Posted June 8, 2009 Author Share Posted June 8, 2009 Re-seated three times, no changes.. Gotta be IMC in this case then? Quote Link to comment Share on other sites More sharing options...
dinos22 Posted June 9, 2009 Share Posted June 9, 2009 try another CPU Quote Link to comment Share on other sites More sharing options...
Massman Posted June 9, 2009 Share Posted June 9, 2009 I've had the same issue on my Gigabyte X58-Extreme motherboard when I was benching under LN2 for the first time on i7 (so a couple of months ago). The third channel wouldn't work, so I had to do with 2 memory sticks instead of three. After the session, I changed setups ... as in: changed motherboard. So with everything else kept the same, I got my third channel back. Quote Link to comment Share on other sites More sharing options...
dinos22 Posted June 9, 2009 Share Posted June 9, 2009 lol good one not getting easier for OP though hahah Quote Link to comment Share on other sites More sharing options...
t0mz0r Posted June 9, 2009 Author Share Posted June 9, 2009 try another CPU Mhmm, I can try another i7 when I get hold of one - as I said in #0, atm I only have some W35xx's as alternates, and they're not doing this. I've had the same issue on my Gigabyte X58-Extreme motherboard when I was benching under LN2 for the first time on i7 (so a couple of months ago). The third channel wouldn't work, so I had to do with 2 memory sticks instead of three. After the session, I changed setups ... as in: changed motherboard. So with everything else kept the same, I got my third channel back. I loose a channel on all mb's tho.. Although, come to think of it, the whole memory detection thingie has only started happening by moving to higher frequency ram. Quote Link to comment Share on other sites More sharing options...
dinos22 Posted June 9, 2009 Share Posted June 9, 2009 i damaged my 2000GTs with too much vdimm i *think* because i can still get the board to boot with tripple channel and then dual channel by going past 1.72vdimm however i cannot any longer make the ram stable even at stock settings with 8xinstances of HyperPi for example it's meeting a very painful slow death i guess.....electron microtion or whatever the know-it-all call it is accellerating heheh Quote Link to comment Share on other sites More sharing options...
Massman Posted June 9, 2009 Share Posted June 9, 2009 What motherboards have you tested, Tom? Quote Link to comment Share on other sites More sharing options...
t0mz0r Posted June 9, 2009 Author Share Posted June 9, 2009 What motherboards have you tested, Tom? Asrock X58 Deluxe Asus Rampage II Extreme EVGA X58 SLI (the non-Classified one) Gigabyte EX58 Extreme Intel DX58SO Haven't had the Xeons thru all of those tho Quote Link to comment Share on other sites More sharing options...
Massman Posted June 9, 2009 Share Posted June 9, 2009 And with all those boards, you lose the third channel with this particular cpu? Regardless of what memory kit used? Quote Link to comment Share on other sites More sharing options...
t0mz0r Posted June 9, 2009 Author Share Posted June 9, 2009 Yeah. It sortta varies from board to board how high frequency can be run stable, i.e. the Rampage II takes point in being able to run all three channels stable at 1333 where as the Asrock (which I'm currently on) needs to be "all auto" in order to run crash-free. That board won't run the W35's, and seated in the Rampage II there are no memory detection issues at all. My 1866gt Corsair kit is about a month old, and I got the OCZ blades about a week back. Quote Link to comment Share on other sites More sharing options...
K404 Posted June 9, 2009 Share Posted June 9, 2009 I was back at the testing today and I managed to get the RAM down to 1 channel in some situations. If its reproducable on demand.. and for my situation im fairly happy that I can-, would that not suggest an instability or limitation rather than degredation? Not tried under cold. Quote Link to comment Share on other sites More sharing options...
t0mz0r Posted June 9, 2009 Author Share Posted June 9, 2009 I kinda have hunch that mine would work (on all three channels) under cold, gonna see if I can get it tried later today Quote Link to comment Share on other sites More sharing options...
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