Question RAM post failure

[rowancoates]

Good Afternoon All.

Ive had this PC for approx 5 years so if the answer is "your motherboard is old and crap" i'll tolerate that
Approx 8 months ago my PC started to fail POST (one long beep + restart), it was kindly fixed with a BIOS update plus ram slot 2 seemed to be partly to blame and so my RAM was moved to slot 4 (Previosuly: Kingston 99U5471-054.A00LF 1x8GB ) It was never clear even after subsequent investigation what this issue was.

I have just installed new ram (Corsair 2x8GB as below). In slots 3 and 4 it will boot happily and BIOS reports 16gb available, however on speed tests i repeatedly get the warning: "Performing below potential (10th percentile) - ensure that a dual+ channel XMP BIOS profile is enabled"

Three questions:

1. im aware that the RAM is sitting in a black and grey slot, which usually means they wont thread, however the BIOS reports ram at 16g... does this mean that it can detect both but wont use them together, or is it just lying? (ANSWERED)
2. I cant find a RAM XMP in bios (i have one for GPU and CPU but not ram) is that because my mobo is too old for this to exist, or is it because im being a doofus and cant find it? (ANSWERED)
3. The big question, why are the other two slots failing post? (if i move the ram to either slot 1 or 2, i fail to POST)

I have tried disconnecting GPU/HDD/SDD, the ram fails to post even as a single stick in either of these slots.

My setup is:

MOBO: Gigabyte GA-Z97-H
CPU: Intel Core i5-4690K
GPU: Nvidia GTX 750 Ti
SSD: Kingston SSDNow V300 120GB (primary)
HDD: Toshiba DT01ACA200 2TB (storage only)
RAM: Corsair Vengeance DDR3 1600 C10 2x8GB

Thank you all in advance.

(edit: post edited as i was kindly informed i was using the wrong numbering system for the RAM slots).

 

[jojesa]

What's the speed of your current RAM and what's the speed that is running?
You could check with CPU-Z.
If your RAM is installed in a black and grey slot, then they are not located in slot 3 and 4 as you mentioned above.
The RAM slot close to the CPU is slot 4, then slot 2, then slot 3 and last slot 1.
For the RAM to run in Dual Channel mode on that motherboard, it should be installed in the two grey slots (slots 1&2) or two black slots (slots 3&4)...otherwise will run a bit slower.
That's why you see the message "Performing below potential"

To enable XMP, go to the BIOS and Enable "Extreme Memory Profile (XMP) under MIT tab.
Select the Memory profile that matches the speed of your RAM.
Save & Exit.

 

[rowancoates]

Good Afternoon.

Thank you for your reply

1. apologies you are correct they are currently in slots 1+2 as per that numbering system. Moving either RAM card into slot 3 or 4 (earest the CPU) causes the anonymous POST failure that i described above.
2. I have found and enabled XMP, many thanks for your assistance on this, no change to the RAM (though it has increased my processor speed some, as expected i suppose).

https://ibb.co/n1tMZ29

cpu hosted at ImgBB

Image cpu hosted in ImgBB

ibb.co

The grey and black are alternated, as in the photo above.
CPU speeds also listed there.

 

[jojesa]

You 1600MHz RAM is running at its default clock speed 799.9 x 2 = 1599.8MHz.
Like I previously stated, the RAM could perform a little bit better in Dual Channel with both RAM modules on the grey or black slots.
Since the RAM modules are located one in the grey slot and another in the black slot it will run in Single Channel mode.
If you cannot configure the RAM in Dual Channel then there could be an issue with the RAM or motherboard.

 

[rowancoates]

Good Evening

Many thanks.

Sorry i now realize i worded my initial post badly. So the reason its in those particular slots is if i use the other two the computer fails POST (one long beep), this happens with both the new ram, a single chip, both chips or using my old ram.

My question (badly worded, i apologize) is any idea why those other two slots might be failing POST?

(i have adjusted my inital post to make it clearer)

 

[jojesa]

Good Evening

Many thanks.

Sorry i now realize i worded my initial post badly. So the reason its in those particular slots is if i use the other two the computer fails POST (one long beep), this happens with both the new ram, a single chip, both chips or using my old ram.

My question (badly worded, i apologize) is any idea why those other two slots might be failing POST?

(i have adjusted my inital post to make it clearer)

The motherboard RAM slots could be faulty.