Asus P8Z77-V LK memory trouble

[korpponen]

Hello!

My P8Z77 mobo only recognize half of the installed memory. I have two 8GB Kingston HyperX Red 1.65V (2x4GB)kits, and pc shows only 8GB in bios and windows even if all 4 ram modules are in plugged in. If using 2 ram modules in which ever slot bios shows 8GB but when adding 3rd or 4th module, it still shows only 8GB. Info tool section in bios sees ram modules in all slots.

So far I have tried:

- reseat the ram modules
- have tested all mem slots with single ram module, all modules work in all slots
- have updated bios to latest
- have cleared Cmos
- have tested dram voltages from 1.4 to 1.65V

But can not get all 16GB available.

Any hints and suggestions what to do would be highly appreciated.

P8Z77-V LK mobo
i5 3570K CPU
Kingston HyperX 1600MHz 1.65V (4x4GB) mem
CoolerMaster 750W PSU

 

[LoveMachine]

Somewhere in the Asus BIOS there is an option to disable a RAM channel. I don't remember what it's called, but take a stroll through the options and see if something got turned off somehow. Also, Ivy Bridge is really meant for 1.5V or below RAM voltage. I briefly ran some 1.65V in a pinch, but I don't know what the longterm consequences would be to running higher than optimal voltage.

 

[korpponen]

Both memory channels are enabled.

 

[LoveMachine]

Could be a bad memory channel. My first P8Z77-V (non-LK) had a bad channel and had similar issues. The RMA'd board works fine, but ASUS' service dept is the opposite of competent.

As mentioned, IVB doesn't like 1.65V memory, and undervolting it probably won't work well. Any chance you could purchase or borrow some other 1.5V RAM on the VQHL for this board and try that? Aside from that, I don't have any other suggestions.

 

[korpponen]

Planning to buy 2 8GB 1.5V ram, Corsair Vengeance model which is on the list. Even if that will not sort it out if all mem slots are working at the same time, atleast then I see if the board can go above 8GB.

Tryin first if the shop are willing to change HyperX they sold to this 2x8GB Corsairm actually they should coz' they were the ones who recommended HyperX 1.65V along with i5-3570K. Didn't knew then (just before last christmas) that those are not quite compatible together, but computer shop should know.