CPU Upgrade

[Zockerfreak01]

HI,

I want to change my CPU. From i5 to i7. What do I have to do so that the PC recognizes the new CPU?

Edit: the mainboard is still the same 

Product number: 3WL78AV

[NonSequitur777]

@Zockerfreak01,

Welcome to our HP Community forum!

You can upgrade your HP EliteDesk 800 G4 Workstation with an i7-8700, i7-8086K, or i7-8700K processor, and you don't have to do anything.  Your desktop will recognize it and boot up -perhaps issuing a couple of beeps and resets, but you'll be fine.

Prior to swapping your processor, I would make sure that you got the latest BIOS version (02.27.00 Rev.A) :

Link: HP EliteDesk 800 G4 Tower PC Software and Driver Downloads | HP® Support.

Hope this was helpful.

Kind Regards,

NonSequitur777

[Zockerfreak01]

i got the latest BIOS Version, but the PC dont want to start with the new CPU.

BIOS-Version/-Datum HP Q01 Ver. 02.27.00, 07.12.2023

Desktop Light Code

maybe this can help: The red light blinks three times, and then five, short white light blinks (3 long red, 5 short white)

[NonSequitur777]

@Zockerfreak01,

Three long red followed by five short white light blinks means that your PC doesn't "see" your processor:

Could mean your processor is faulty, but before we get ahead of ourselves, what processor are you trying to fit?  Also, if you can, please take pictures of the front and back of the processor, making sure you black-out the serial number and post them, like this:

Kind Regards,

NonSequitur777

[Zockerfreak01]

Intel Core i7 9700 is the new one

[NonSequitur777 · Accepted solution]

@Zockerfreak01,

Ach so, that explains it then: your desktop is not compatible with 9th gen processors.  The best processors compatible with your PC are the i7-8700, i7-8700K and the i7-8086K.

Kind Regards,

NonSequitur777

[Zockerfreak01]

Hi again,

Is it possible to replace the mainboard and can you give me a tip as to which one would be suitable?

[NonSequitur777]

@Zockerfreak01,

Yes, it is indeed possible swap your HP EliteDesk 800 G4 Tower motherboard with an HP EliteDesk 800 G5 Tower motherboard, as they happen to be identical dimensionally:

And there happens to be one for sale via eBay-Germany: Original HP Elitedesk 800 G5 TWR Motherboard Motherboard | eBay.  You can use your i7-9700 with this motherboard.  This G5 motherboard replacement should have its own Windows license (it is not transferable from your G4 motherboard), so you'll have to see how that plays out.

Hope this was helpful.

Kind Regards,

NonSequitur777