PC behaviour with no CPU

[kyle2kxx]

Hello all! So I upgraded my old system to DDR4 using the Z270 platform. Only thing I upgraded was motherboard, RAM and CPU, however, the CPU has not arrived yet. I built the pc up as much as I could so far, and when I turn on the PSU via the switch, the motherboard lights up as well as all my peripherals, but when I press the power button, nothing happens, nothing, at all. Not even fans (these are plugged in to my board, not my PSU), and not even the power LED lights up. I am a 'little' worried about this, but not 100% worried as I know things like this can differ depending on the chipset. So, is this behaviour normal for the Z270 chipset or is it dead on arrival?

[Theguywhobea]

A CPU isn't optional, of course it's not going to work with no CPU.

[Aggravated Salmon]

check your case PWR_SW +- are connected to the appropriate +- PWR_SW on the motherboard. 

[i_build_nanosuits]

it's normal, nothing can operate without a processing unit.

[Jurrunio]

No CPU = no work. Only a few super expensive mobo can let you access the BIOS without the CPU. All others require one to do anything.

 

How much did you pay for all these though? Please dont tell me the CPU and mobo are both new.

[minibois]

A PC will not turn on without a CPU, just like it won't do anything without RAM and a PSU. These three things are required components to a PC.

[JakeNTech]

The CPU is the brain of the computer. If the computer has no brain it can't do anything, other then light up. 

[Crunchy Dragon]

Your PC can't do anything without a CPU. The only I'm aware would happen is during the POST you will receive an error code for the CPU

[NelizMastr]

It's as much of a plant as a human with extensive brain damage or without brains at all. Completely normal behavior.

 

Any particular reason you went Z270? 2nd hand I hope?

[kyle2kxx]

28 minutes ago, Jurrunio said:

No CPU = no work. Only a few super expensive mobo can let you access the BIOS without the CPU. All others require one to do anything.

 

How much did you pay for all these though? Please dont tell me the CPU and mobo are both new.

I bought new because I don't like to buy anything pre owned.

[kyle2kxx]

23 minutes ago, NelizMastr said:

It's as much of a plant as a human with extensive brain damage or without brains at all. Completely normal behavior.

 

Any particular reason you went Z270? 2nd hand I hope?

I wanted the upgrade to DDR4 (I know the difference is minimal but everything else in my pc is very up to date) and no, I bought new. Why you hope 2nd hand?

[Jurrunio]

Just now, kyle2kxx said:

I bought new because I don't like to buy anything pre owned.

7th gen is actually outdated because it wont be receiving any new CPU, while it's successor, 8th gen, gets 4 core CPUs on i3s and 6 core CPUs on i5s and i7s. It's ok to not buy anything used if you want to, but at their current price, buying 7th gen is like getting robbed.

[kyle2kxx]

4 minutes ago, Jurrunio said:

7th gen is actually outdated because it wont be receiving any new CPU, while it's successor, 8th gen, gets 4 core CPUs on i3s and 6 core CPUs on i5s and i7s. It's ok to not buy anything used if you want to, but at their current price, buying 7th gen is like getting robbed.

This is fine, this upgrade was expensive as I had to buy RAM too amd I was in a bit of a rush so I was unable to save more. However though, I have the RAM now and I don't plan to upgrade for many years so at least when the time comes I'll only need to buy cpu and motherboard

[Aggravated Salmon]

guys did u read the desc he says when he powers on the psu the fan spins and everything but clicking the power button achieves nothing. this is probably a problem with the case IO pins thingy not being connected properly

[Jurrunio]

Just now, kyle2kxx said:

This is fine, this upgrade was expensive as I had to buy RAM too amd I was in a bit of a rush so I was unable to save more. However though, I have the RAM now and I don't plan to upgrade for many years so at least when the time comes I'll only need to buy cpu and motherboard

How much did you actually pay for the CPU and mobo? Currently, an 8400 (6 core CPU) costs $200 and Z370 mobo (because that's the only choice) costs $120 each for the mid-range ones while easily beating the 7600k over and over again, no matter how high the overclock (unless you go LN2)

 

2 minutes ago, Aggravated Salmon said:

guys did u read the desc he says when he powers on the psu the fan spins and everything but clicking the power button achieves nothing. this is probably a problem with the case IO pins thingy not being connected properly

The test wasnt done on a full machine so that tells nothing about I/O connection being fine or not.

[kyle2kxx]

3 minutes ago, Jurrunio said:

How much did you actually pay for the CPU and mobo? Currently, an 8400 (6 core CPU) costs $200 and Z370 mobo (because that's the only choice) costs $120 each for the mid-range ones while easily beating the 7600k over and over again, no matter how high the overclock (unless you go LN2)

 

The test wasnt done on a full machine so that tells nothing about I/O connection being fine or not.

I'm in UK and I wanted i7 as I do more then just gaming. Cost was £150 for motherboard and £270 for 7700k. I wanted coffee lake but only way I could go coffee lake was to go without a PC for several weeks and that's not a option and I had to buy RAM too 

[Jurrunio]

10 minutes ago, kyle2kxx said:

I'm in UK and I wanted i7 as I do more then just gaming. Cost was £150 for motherboard and £270 for 7700k. I wanted coffee lake but only way I could go coffee lake was to go without a PC for several weeks and that's not a option and I had to buy RAM too 

PCPartPicker part list: https://uk.pcpartpicker.com/list/9sTBXH
Price breakdown by merchant: https://uk.pcpartpicker.com/list/9sTBXH/by_merchant/

CPU: Intel - Core i7-8700 3.2GHz 6-Core Processor  (£294.99 @ Ebuyer) 
Motherboard: ASRock - Z370 Pro4 ATX LGA1151 Motherboard  (£109.56 @ Amazon UK) 
Total: £404.55
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2017-12-20 16:13 GMT+0000

 

I'm sorry but you did get robbed. Even better looking and built motherboards cost 130 pounds.

[kyle2kxx]

2 minutes ago, Jurrunio said:

PCPartPicker part list: https://uk.pcpartpicker.com/list/9sTBXH
Price breakdown by merchant: https://uk.pcpartpicker.com/list/9sTBXH/by_merchant/

CPU: Intel - Core i7-8700 3.2GHz 6-Core Processor  (£294.99 @ Ebuyer) 
Motherboard: ASRock - Z370 Pro4 ATX LGA1151 Motherboard  (£109.56 @ Amazon UK) 
Total: £404.55
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2017-12-20 16:13 GMT+0000

 

I'm sorry but you did get robbed. Even better looking and built motherboards cost 130 pounds.

I got Asus ROG strix z270 for the aura to match my Asus 1080 O8G. But so, do you think my motherboard is broke or do you think it is reacting this way due to no cpu? Because usually no cpu will still power fans etc (I think?) but yeah, nothing is happening at all when I push power button, but hitting the switch lights up the motherboard and peripherals 

[Jurrunio]

1 minute ago, kyle2kxx said:

I got Asus ROG strix z270 for the aura to match my Asus 1080 O8G. But so, do you think my motherboard is broke or do you think it is reacting this way due to no cpu? Because usually no cpu will still power fans etc (I think?) but yeah, nothing is happening at all when I push power button, but hitting the switch lights up the motherboard and peripherals 

That expensive mobo sure takes a big hit on value

CPU: Intel - Core i7-8700 3.2GHz 6-Core Processor  (£294.99 @ Ebuyer) 
Motherboard: Asus - ROG STRIX Z370-F GAMING ATX LGA1151 Motherboard  (£179.98 @ AWD-IT) 
Total: £474.97

£50 for 50% more cores

 

Anyway on your situation, it's quite hard to tell whether it's fine. Normally a mobo shouldnt turn on any peripherals when the PC is turned off, but then there could be BIOS options to leave the lights on when the machine isnt running. You dont have a CPU yet so you cant look into the BIOS and prove this theory.

[kyle2kxx]

9 minutes ago, Jurrunio said:

That expensive mobo sure takes a big hit on value

CPU: Intel - Core i7-8700 3.2GHz 6-Core Processor  (£294.99 @ Ebuyer) 
Motherboard: Asus - ROG STRIX Z370-F GAMING ATX LGA1151 Motherboard  (£179.98 @ AWD-IT) 
Total: £474.97

£50 for 50% more cores

 

Anyway on your situation, it's quite hard to tell whether it's fine. Normally a mobo shouldnt turn on any peripherals when the PC is turned off, but then there could be BIOS options to leave the lights on when the machine isnt running. You dont have a CPU yet so you cant look into the BIOS and prove this theory.

Oh damn! The only 8700k I found was £380/390 and yeah I thought that but I guess a PC will behave strange with no CPU it's almost like it doesn't know what to do. On another note though, the motherboard should be broke if it is lighting up etc. I will try put a fan in to the PSU and press power button and see if a fan lights up. At least this way we will know 100% if the PWR_SW is in the right way which I am almost sure it is.