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- Z420 won't boot after upgrade to 8GB ram
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09-24-2018 03:42 PM
> Posted: 06-01-2017 08:56 PM
09-24-2018 04:57 PM - edited 09-25-2018 05:13 PM
Greetings,
Welcome to the forum.
I am not a HP employee.
Your PC requires DDR3, UDIMM (Unbuffered), ECC memory. The supported memory speeds are: 1066-MHz, 1333-MHz, and 1600-MHz DDR3.
You purchased non-ECC DDR3 memory (Link to memory specifications) running at 1866 MHz.
The new memory is not compatible with your motherboard. You will have to return this memory to the seller.
I would try Crucial Memory (Link) for compatible memory. Select your PC's product number from the drop down lists or use the memory scanner. You can also check HP Part Surfer (Link) for compatible memory modules.
Use your PC's product number instead of the generic Z420 ID at HP Part Surfer to zero in on your specific system.There are many Z420 systems.
Regards
09-25-2018 01:44 AM
> You purchased non-ECC DDR3 memory (Link to memory specifications) running at 1866 MHz.
The SPD (Serial Presence Detect) chip on most sticks of DDR3 RAM defines the various speeds that are compatible with the RAM.
For example:
Type~DDR3
Size~4096 MBytes
Manufacturer~Corsair
Max Bandwidth~PC3-10700H (667 MHz)
Part Number~CMX4GX3M1A1333C9
Week/year~25 / 10
Timing table
~Frequency~CAS# Latency~RAS# To CAS#~RAS# Precharge~tRAS~tRC~Voltage
~~JEDEC #1~444.4 MHz~6.0~6~6~16~23~1.500 V
~~JEDEC #2~592.6 MHz~8.0~8~8~22~30~1.500 V
~~JEDEC #3~666.7 MHz~9.0~9~9~24~34~1.500 V
Do you see that while the maximum bandwidth is PC3-10700H (667 MHz)
this stick of RAM is capable of operation at either or 2 slower clockings.
There is an extremely-strong possibility that the SPD on your 1866 MHz RAM also defines a compatible lower clocking, namely one that is compatible with your motherboard.
But, check the number of RAM chips on your sticks, e.g.,4 or 8 per side, and either single-sided or double-sided, and compare that with any RAM that does work on your motherboard.
Also, if you "mix" different speeds of RAM, put the slowest RAM into slot #1.
That way, the motherboard may clock all the RAM at that slowest speed.
Putting the "fast" RAM into slot #1 may cause problems, if "slower" RAM is in the higher-numbered slots.
09-25-2018 07:54 PM - edited 09-25-2018 09:05 PM
Hi,
It appears Abelna may have purchased incorrect memory.
Abelna, please go back to the HP factory hardware configuration.
Tell us if your PC can boot to the Windows Desktop after reinstalling the factory RAM.
Regards