Strange Memory issue

[Chanfron]

Hi

At the start of last month I build myself a new PC using the following components all purchased via Scan

Core i7 950 http://www.scan.co.uk/products/intel...io-130w-retail
Asus P6X58D-E http://www.scan.co.uk/products/asus-...-sata-raid-atx
Corsair 6Gb Triple channel kit http://www.scan.co.uk/products/plus-...-9-9-9-24-165v

Built machine, installed Win7 HP 64bit drivers etc, reinstalled all my games and everything was great, about two and a half weeks ago I was checking something and I noticed that the system was only showing 4Gb of ram and not 6Gb, rebooted and checked bios and it also said 4Gb, shutdown and opened up and checked memory, turned back on and bios said 6gb.

Since then I have been monitoring the memory, it would randomly sometimes boot with 4Gb and sometimes 6Gb, all memory settling in the bios were set to Auto, then for about a week it was 6Gb everytime I booted up.
Then back to 4gb, I have run memtest on the machine when it show 4Gb and 6Gb and get no failures but one odd thing is that memtest lists 3x2Gb modules when it is only showing 4Gb available memory.
For the last week I have set the bios to use the XMP memory profile and it will consistently list 4gb on the first boot, shutdown and restart and 6Gb will show.

The memory is the TR3X6G1600C9 kit and it is listed as being compilable with the motherboard, I have also tried using the mem ok button on the motherboard but that made no difference.

Any ideas what may be causing this issue, I get no errors with memtest and no problems with win 7, the motherboard was shipped with the latest bios.

Other hardware being used
GF250Gts
Corsair HX 850W PSU
1TB WD Hdd
X-Fi Titanium Fatality
All stock settings and no overclocking.

[kalniel]

A bad contact in between the CPU and socket can cause this. Make sure you've not over-tightened the HSF, and check that no parts of the motherboard are being shorted. Are you using the stock Intel HSF?

[Chanfron]

I am using the Akasa Nero S Premier cooler http://www.scan.co.uk/products/akasa...m2-am2plus-am3 I can try slackening off the retention screws slightly and see what happens.
If that does not help I will remove the HS and CPU and refit.

I do plan on adding A GTX480 to replace my GTS250 at some point as I will be replacing my old CRT monitor with TFT one at Xmas.

[kalniel]

If you do remove, be extremely careful when you do so, then very carefully inspect the socket on the motherboard - you will need some kind of magnification, possibly macro photography. And look for bent or odd looking pins. You can also check the CPU and check the pin imprints - there should be one in near the middle of every pad.

If no problem with the socket then try adding some insulation to the backplate - rubber washers or wrapping in PVC tape.

[ChrisLUFC]

I had a similar problem a few months ago. Ever since i ordered the board i had random blue screens relating to memory, anyway i never used that machine as it was only as a test machine before i rolled out Win7 to the rest of the domain. i came to plug it back in after being in storage for 2 months to use as a digital signage host and after 4 days of it being plugged into a UPS the M/B had blown.

RMA'd to scan and they said it had a bent pin (probs the cause of all my problems) but i was rejected for the RMA as bent pins = no RMA

So if you do have a bent pin im not sure how you would go about getting it replaced. You may have to prove it was like that when you got it which im not sure how you can achieve (i told them i had problems since day 1 with the board and it didnt make a differance) . I just cut my losses even though it was an expensive board.

[=assassin=]

I had the issue with missing memory with a 4Gb kit with my 875k, only occured on a completely cold boot though, was found out to be a memory issue with one of the sticks luckily, so got it replaced, and saved having to mess around taking the heatsink off the cpu again.

[Chanfron]

I think I will remove the motherboard and then remove and refit the CPU, I did slacken the Heatsink retention screws slightly and both yesterday and this morning from cold boot it has registered the correct amount.

Not 100% convinced this has fixed it, I have also been been checking my CPU temps and I think they are too high, according to coretemp and realtemp my idle temps are 40ºc on each core and about 71ºc ish when using prime95 with in-place large fft settings (max heat/power etc).

[Chanfron]

4Gb on cold boot this morning so slackening the screws has not helped.

[Chanfron]

I removed the motherboard and removed the CPU saturday evening, checked the CPU and socket, cannot see anything wrong, used a magnifying glass to look at the socket and the bottom of the CPU and cant see anything wrong with the pins in the socket and all the pads on the CPU look to have a contact mark on them.

Refitted everything and get 6Gb on first boot, also got 6Gb on cold boot on sunday so will now monitor and see how it goes.

[Chanfron]

4Gb on cold boot when got home from work so still not fixed, will have to see if I can aqqure some different memory to test.

[Yellowbeard]

Have you tried all of the troubleshooting steps outlined HERE?

[Chanfron]

Have you tried all of the troubleshooting steps outlined HERE?

Oooooo thanks not seen that post, will have a look tonight, I have not altered any of the voltages in the bios, all are set to Auto or whatever the default was.

Got 6Gb this morning on cold boot.

edit - is there any recommended bios settings for the memory kit I have, the TR3X6G1600C9 kit no overclocking.

[Yellowbeard]

You cannot run the memory you have at AUTO settings. In your BIOS, try enabling the XMP profile for the memory.

[doddsy]

I had a similar problem with a Gigabyte X58A-UD3R board. Generally cold boots would show 4gb, restart and 6gb would be there. Gigabyte eventually 'fixed' the problem with a BIOS update that restarts the system while booting if the full compliment of memory is not available.

[Chanfron]

You cannot run the memory you have at AUTO settings. In your BIOS, try enabling the XMP profile for the memory.

I have already tried the XMP profile (see my original post) and it will almost consistently show 4Gb on cold boot, shutdown and power on then give 6Gb, occasionally will post 6Gb on cold boot.

I tried a few things listed on the troubleshooting page and on the forums that it came from, manually set the memory timings to match what the modules when set to XMP profile, not sure which voltage settings I should use but tried several suggested on those forums for similar setups to mine.

I either get overclocking failed warnings on reboot or the bios completely resets on reboot so I have just set it back to XMP profile.

I am starting to think I have bought the wrong memory, I was planning to do some overclocking in the future which is why I went for this memory, I will gladly forget the overclocking to get rid of this issue.
Would I be better getting some different modules that can be used with auto settings, if so can any be suggested.

I will create a post on that i4memory forum and see if I can get any help.

[Chanfron]

Still have issues, new bios has been released and has been installed as of yesterday, for more info see my post here http://i4memory.com/f54/i7950-asus-p...85/#post137753

This is getting very frustrating, I will try adding post to corsair forums and asking Scan for help but if the problem is not rectified within the next 2 - 3 weeks I am going to RMA the lot as not fit for purpose.

Either something is not compatible or is faulty, I am a a newbie when it comes to messing with memory timings but since I have been building and repairing computers for a living for the past 10 years I am not new to the game.

Last time I had memory issues like this was in the days of Pc133 memory where some boards would only show half the installed memory.