HP Z420 mobo for custom PC

[Aussie_Pezza]

Hi all,

I am building a custom PC with a mobo from a HP Z420 with a Xeon 2690v2 (it is compatible with my board as its a 618263-003 mobo) and 64gb Non ECC ram. It is in a Silverstone case with a H115i pro AIO liquid cooler and  HX850i psu.

On finishing the build and switching it on, I have either the following problem. 

1 - Nil graphics. I have tried both a RX 580 and GT970 in both PCIe16 slots and nothing. 

or

2 - Maching just not firing up, hence no graphics, not even getting to BIOS.

But, here's where it is strange. Everything powered off the PSU runs fine. Case fans, AIO pump/fans, GPU fans. I even have the solid blue light on the mobo showing its in the on condition. I have taken out all the ram and when powered on I have the red led flashing 5 times in 5 secs with the 2 sec break (so it detects an error). I put the ram back in (tried 1 by 1 in the correct position) and back with solid blue light. I hear the hard drive working away too, but no display. 

I don't even know what the problem is or what else to try. 

I am thinking it may be the ram as it is not ECC ram (and they specify to use ECC ram, but others on these forums have success with non ECC ram), or is my mobo dead, or the CPU dead. I am beat and don't know where to go next.

Any suggestions please. Thank you

[DGroves]

first, workstation related questions should be posted in the "workstation forum"

https://h30434.www3.hp.com/t5/Business-PCs-Workstations-and-Point-of-Sale-Systems/bd-p/Business-PC-W...

second trying to adapt a workstation board into a diffrent case is not a beginers task

third, before atempting something like this do your research before starting this includes reading the z420 service manuals and visiting sites and asking BEFORE DOING ANYTHING if there are any known pitfalls 

http://h10032.www1.hp.com/ctg/Manual/c04205252

the z420 uses  PC3-12800E 1600MHz DDR3 Unbuffered ECC DIMMs, NOTE THE UNBUFFERED ECC, this ram is not the same as most ram used in consumer pc's

http://isvpatch.external.hp.com/HPPTF/drvlib/docs/Z420_Memory_Configurations.pdf 

your z420 motherboard uses a non standard power supply/pinout that does not follow the ATX standard, however there are adapters to convert a ATX supply into the HP pinout (google HP z420 ATX adapter)

the HP z420 uses 

the z420 uses a ambient tempture sensor which is embeded into the power switch harness, you will either have to remove this sensor from the pwr harness or make a sensor yourself or the case fans will allways run a max speed

the motherboard mounting holes are not fully ATX compatable, as such your case may or may not have spacersholes that match the motherboard mounting points

the z420 may use a non standard front panell usb 3.0 pinout (i don't recall check the service manual) 

the z420 uses a case where the back I/O plate is stamped out and is not a replaceable plate like consumer pc cases, as such you need to make one yourself

there are a few other items, but the above are the main ones

[Aussie_Pezza]

Thanks for your response.

I am already aware of all those issues and have already factored them into my build. I have the PSU adapter, the temp sensor I made out of a NPN transistor following instructions from another post. There are 3 holes that don't match as per ATX form factor but that's no issue, and you can buy aftermarket I/O plates for the rear. 

I am guessing my problem is the RAM, this one slipped thru the nets. 

I am just interested to hear if anyone else has had similar problems, as I have read on these forums people have been successful with non-ecc ram.

[Aussie_Pezza]

ECC ram installed and now boots fine. The ram was the problem.

Next problem is getting the thing to boot with my RX580gpu. Does not like that. It boots fine with a **bleep**ty old Nvidea gpu. 

I will try disabling secure boot and enabling legacy and see how that goes.

[Keepit69]

Hi, I am running my z420 zombie in factory case without issues, with h100i looking for case too, its pretty nasty work right now. Let me know your choice.

Few points:

dont see any temperature sensor, is that for no “f1 for boot”? I am running 24/7, now without any original fans, only one extra 120mm “case” fan used and pluged into pump too...no need

Adapter is for 11v standby line and to convert standard atx psu into hp pinout, there are different pinouts and voltages! And I used some cheap server ecc HP rams, look for lokal sales, its like dirty cheap. And use proved gpu, there is list, its good for drivers and for your mental health, happy user hp quadro p100, machine is the beast. Do at your own risk! This is not manual!

[DGroves]

the HP xw and "z" series workstations have a ambient air temperature sensor embeded into the cable for the power button

if this sensor is not connected the HP bios will ramp the case fans up to full speed

if the case fan(s) are missing you will get a F1 error during boot, same for the front USB/Audio 

[Keepit69]

Thx, got it now.