Only 4GB of 6GB detected

[Zelroy]

My new computer includes:

• Asus P6T Deluxe V2, 0504 BIOS
• Intel Core i7 950
• 3 x G.Skill F3-16000CL9-2GBTD DDR3-2000

I haven't overclocked the machine or touched BIOS settings in any way.

The problem is that both BIOS and OS detect only 4GB of the RAM. However, if I power off and then quickly power on again, both BIOS and OS (and CPU-Z etc) detect all 6GB of the RAM normally. The computer hasn't ever crashed or anything yet. I haven't tried a memory tester utility, either.

I'm just guessing but this smells like a BIOS setup problem to me. My know-how is not enough to solve the problem. How do I fix the situation, please?

[Tradesman]

Regardless you may have problems with the GSkill RAM to run at 2000. Anyway, make sure the RAM is well seated in slots 1,3,5. In the BIOS check your basic RAM timings and ensure they equal the specs for your specific set. Looks like you have the latest BIOS which is good. If the problems continue might check your PSU, might try replacing the CMOS battery, or even going backwards to the 0406 BIOS. Can also try running each stick of RAM under memtest individually, may have a stick that is on the fringe of bad/going bad

[Zelroy]

In the BIOS check your basic RAM timings and ensure they equal the specs for your specific set.

What are these timings and specs supposed to be?

[Tradesman]

Based on the model you posted. I'm guessing it's actually the F3-16000CL9T-6GBTD, the Trident, the specs on that are 9-9-9-24, 1.65volts, command rate 2T. If I'm wrong either let me know, or you can get the specif specs for what you have at GSkills web site (should be on the package, if you still have it.)

[Zelroy]

The other timings match your specs, but according to CPU-Z, Command Rate is 1T, not 2T. However, there is no setting in BIOS to change it. How do I set the right Command Rate?

[Tradesman]

Believe on the P6T it's in the advanced timings, will see if I can pull out a manual when I get back later this afternoon or early evening, should be back by 7PM PST

[Tradesman]

Called a friend, believe it's listed under DRAM TIming Rate and you would want to set it as 3N to achieve 2T. May also want to look at tRFC and kick it up. Got to run , will pull manual this PM

[Zelroy]

I changed it to 3N but there was no change in Command Rate. I didn't see a setting called "tRFC".

[genetix]

Actually spec on this would be 1T on ( Screenshot CPU-Z EPP/XMP ). So, Leave the refresh rates alone or that's at least what the EPP says. """Board supports only 1603 Mhz officially according to my checkup. However, there's a lot of people out there seems to be running this same memory and board on ~1730Mhz and on CL7 which actually sounds pretty good to consider CL9."""-Might be old info

About above Comment on 'Well, seated on memory controller' You might try adding them to slots 2-4-6, if for some reason board would have some kind 'cosmic' contact error on one of the memory slots.

Anyway, should be: 9-9-9-24-1T
If you go to BIOS there's in 'Advanced'-page > 'Ai Overclock Tuner' > press enter on it should find 'X.M.P.' which indicates Memory profile in memory choose that and F10 > save settings

(if this fails and you get black screen press power button for 5 seconds > computer shuts down > power it up (it will boot twice) and let you press F1 to get back to BIOS 'overclocking has failed message will appear'.)

[Zelroy]

I didn't find "X.M.P." from the BIOS, either.

I tested the memory with memtest-86 v3.5. Individually, each module passes the test in the first orange slot. When all modules are installed, Test 0 freezes on 7%, when the last module (4 GB - 6 GB) is being tested. I guess there is a hardware failure after all. Maybe it's the motherboard, maybe the psu... I'll let the system builder figure it out.

[genetix]

Nah, don't fall just yet.

The X.M.P. profile is there also called 'Memory profile' or it could read 'Memory Performance Profile' you can be sure on that. So check again there should be options 'Auto', 'CPU based OC' 'X.M.P.' & 'Manual' on that option I pointed you at. Just try to find it I just readed 4602 manual of your board and it's there.

Correction: My BAD I though it was on 'Advanced'-section Look screen below.
http://benchmarkreviews.com/images/r...alm_bios_5.jpg

The latencies on 'Auto' as now probably would actually freeze the system. The seeing 4-6GB total is weird, but this could also be caused by bad latencies. Also freeze might happen on XMP setup. Sad news there is that we are dealing with very very advanced equipment, if that fails would need to adjust latencies manually a bit. however, none of this explains missing 2GB so try the secondary slots.



I'd count PSU out of it. Motherboard maybe in the controller. (but I can assure you I've seen these errors on every single board I come across here with bad latencies or simply bad voltages or something)
Did you test the second slots? (2-4-6)

[Zelroy]

Well, I already sent the computer back.

I didn't test the seconday slots, because the manual said something about Triple Channel being enabled on the orange slots, and because all the slots should work in any case.

I hope the guys at the workshop know what they're doing and won't keep my new computer there too long... Maybe I should try to send your suggestion to them just in case. They should have gotten it right the first time though, before sending the stuff to me.

[genetix]

Perhaps, but if that controller has cosmetic contact error on it. You did exactly right thing to send it back.

I'm just over advice style of person and never quit before it either works or I know where the exact problem is on before I send something back. Basically, if box returns as the same I bet they just tweaked latencies or edited BIOS a bit sadly then we could of solve it clean, if new box or something they probably will change memory/motherboard then there really was an issue on board.

Anyway, hope you'll get soon enough everything up and running again.