Help? Asrock Z77 Extreme 4 unable to POST -- Errcode 55

[magix]

I'm assembling a recently purchased Z77 Extreme4 into a PC.

Without memory, it powers up and displays code 53, but nothing displays on-screen.
With RAM installed, it powers up, shows code 55, then powers down and repeats the cycle until I hold the power button 7 seconds.

I first assembled the machine with Patriot Viper 3 DDR3 2x8GB 1866MHz (PV38G186C9K).
When it threw the error, I bought some Kingston HyperX Blu DDR3 2x8GB 1600MHz RAM to try as well (KHX16C10B1R/8 x 2).
Change of memory sets didn't fix the problem.

This happens regardless of whether there's one DIMM or two installed, and regardless of the slot(s) they're installed in.
I've also tried using one of the pair, then the other when testing one-at-a-time to rule out defective RAM.

Manual says code 55 is "No usable memory installed".
How can I overcome this problem or identify what's going wrong?

Thanks in advance.

[parsec]

Neither of the memory models you tried are listed in your boards memory compatibility list. Using other memory will be hit or miss if it works or not, and in your case it seems to be a miss. That error message is unfortunately accurate.

Memory manufactures may say a model will work with a certain CPU or chipset, but those are general statements. I've always used memory from a boards qualified list, and it always worked for me.

Check the boards memory list below, hopefully you can return yours for something on the list:

ASRock > Z77 Extreme4

[- wardog -]

Try booting after placing only one stick of the Kingston in the DDR3_B2 slot.

You should also clear the bios prior to booting with it installed.

If it doesn't do anything in the DDR3_B2 slot, place it in the DDR3_A2 slot and retry.

[magix]

Neither of the memory models you tried are listed in your boards memory compatibility list. Using other memory will be hit or miss if it works or not, and in your case it seems to be a miss. That error message is unfortunately accurate.

The reason I went for the Kingston is that it looks like it's the same as one of the ones on the compatible list, except for the fact that it's got the red heat spreader. (Model differs only in the addition of 'R' at the end.)

I went hunting for the ones on the compatibility list and came up empty at any nearby retailers, or turned up ridiculous prices for only two I could find online.

/me sighs

I guess I'll have to try again...

M