[SOLVED] 2 slots DD3 memory not recognised after cpu upgrade from i7 920 to xeon 5670

[Bigg1es]

Ive just upgraded my i7 920 CPU to a Xeon 5670 and 2 slots of memory are no longer recognised. They were working perfectly before the cpu change so there are no issues with motherboard or the physical connection.

The motherboard is an Asus P6T SE . The 4 slots that are working contain 4x 2GB corsair TR3X6G1333C9 1333 mhz ( these came with the PC )
The Memory not recognise is an upgrade i bought in 2017 and is Crucial 8GB Kit (2 x 4GB) DDR3L-1600 UDIMM

I am not technical at all and its difficult for me to figure out the problem, however my limited brain capacity is thinking there is a difference in the speed.
I understand an X5670 is compatible with DDR3 800/1066/1333 memory types .

Is the "1600" in my Crucial memory spec the speed and am I right in thinking that's why its not recognised and I must replace it with "1333" ?

Is there anything else I need to watch out for in the specs if I am ordering new memory or is all DDR3 1333 desktop memory the same?

I don't want to spend a lot on an ancient system, so may look at second hand . I see DDR3 1333 4gb for 12.89 GBP on ebay, so if I buy a few of those will it work?

I note that sticks of 4gb and also 8gb are available, but somewhere in the back of my mind is the though that my set up is max 24 GB so I should stick to 4gb sticks. is that right?

Any advice appreciated.

 

[SamirD]

The x5670 supports all the same memory as the i7-920, so a suspect that either the cpu you got is bad or it isn't seated correctly. If it isn't seated correctly, some of the memory channels may not work correctly and because of that.

I would remove the cpu, check to make sure nothing is obstructing or damaged on any of the pads of the bottom of the cpu, and then carefully reinstall it and check again.

 

[Bigg1es]

Thanks Samir, that sounds perfectly possible. Its the first time I have had a CPU out so its quite possible its not fitted correctly. It was also second hand , so may have a fault. I will re seat it and see what happens

 

[SamirD]

Thanks Samir, that sounds perfectly possible. Its the first time I have had a CPU out so its quite possible its not fitted correctly. It was also second hand , so may have a fault. I will re seat it and see what happens

Just take your time and do it carefully. It's rare that cpus go bad so I'm pretty confident it is a seating issue. If it does not work, put your i7 back in and confirm that all the slots work again. If they don't, something might have broke.

 

[Bigg1es]

SamirD, your a genius, you were spot on, it was a seating issue.

I carefully examined then removed the CPU. By eye I could see nothing wrong and bar the memory the PC was working fine, but when I put it back in and booted up, it recognised all 6 memory slots.

The only other thing I changed was at the same time I reseated the cpu, I also swapped round 4 of the memory slots. I don't think that was what did it though as there was nothing wrong with the seating before.

I now have all 6 cores working perfectly and all my memory as well.

Thanks for your help, Im glad I joined the forum