[Solved] MSI B450 Tomahawk CPU compatibility

ikcdab

ikcdab

ikcdab

Associate
Joined
12 Oct 2018
Posts
11
I have just built a new system:

MSI B450 tomahawk motherboard
AMD ryzen 5 2600 (without onboard graphics)
Nvidia gtx 1050 GPU.
PSU with 4 pin CPU power supply connector.
Suitable RAM

When I power up, the system appears completely dead, no MB LEDs, no fan activity anywhere. I have had the MB tested by the supplier and it is ok. The GPU has been working previously in another PC. The PSU is brand new. All is see is the power LED on the GPU come alive.

Two questions:

1. Is this CPU ok? The MB manual says that it needs ryzen 5 with Radeon Vega graphics. My CPU doesn't have that, is this a reason for the mb to appear dead? Do I need to use a CPU with the onboard graphics?

2. My PSU has a 4 pin pci plug for cpu power, but the mb has an 8 pin socket. Does this matter? Will the CPU work ok with just the 4 pin plug in the 8 pin socket?

if its not either of these, then what on earth is causing the whole thing to appear completely dead? No life or activity at all, apart from the GPU power LED lights up.

Many thanks
 
ikcdab said:
I have just built a new system:

MSI B450 tomahawk motherboard
AMD ryzen 5 2600 (without onboard graphics)
Nvidia gtx 1050 GPU.
PSU with 4 pin CPU power supply connector.
Suitable RAM

When I power up, the system appears completely dead, no MB LEDs, no fan activity anywhere. I have had the MB tested by the supplier and it is ok. The GPU has been working previously in another PC. The PSU is brand new. All is see is the power LED on the GPU come alive.

Two questions:

1. Is this CPU ok? The MB manual says that it needs ryzen 5 with Radeon Vega graphics. My CPU doesn't have that, is this a reason for the mb to appear dead? Do I need to use a CPU with the onboard graphics?

2. My PSU has a 4 pin pci plug for cpu power, but the mb has an 8 pin socket. Does this matter? Will the CPU work ok with just the 4 pin plug in the 8 pin socket?

if its not either of these, then what on earth is causing the whole thing to appear completely dead? No life or activity at all, apart from the GPU power LED lights up.

Many thanks
Click to expand...

The motherboard should work with any RyZen AM4 CPU, id say its the PSU, you probably need the 8 pin, the 4 pin probably isn't enough, you can pick up an adaptor to convert a couple of the molex connectors into an 8 pin EPS connector for the motherboard.

Even if the CPU was dead, the board would still fire up, lights, fans etc, it just wouldn't post, as the board has been tested, that's completely a PSU fault, hope you didn't skimp on a generic budget PSU.
 
If your psu doesn't have an 8 pin cpu connector then you probably shouldn't be using it. What make/model is it ?
 
Thank you for the previous replies.
I bought the psu from Amazon:
Switching Power Supply PSU 600W ATX with 12cm Silent Red Fan / for PC Computer / iCHOOSE


 
I have also ordered a 4 pin to 8 pin adaptor.
I an waiting for the mb to be returned from the supplier.
What I was surprised about was the compllete absence of any life at all. Not even an led on the mb or any fans spinning up.
 
^^That thing is far from Ace. Do yourself a favour and buy a semi decent power supply.

Something like a Bitfenix Formula 450W or Corsair CX/M (Grey label) will power that system. The one you have now is a ticking time bomb.
 
lee32uk said:
^^That thing is far from Ace. Do yourself a favour and buy a semi decent power supply.

Something like a Bitfenix Formula 450W or Corsair CX/M (Grey label) will power that system. The one you have now is a ticking time bomb.
Click to expand...
Why do you say it's a ticking time bomb? Is it not going to work or do you say it's going too blow up?
 
Lordgrayone said:
Never heard of the brand so probably cheap an nasty and likely to go pop, 650W power supply without an 8 pin cpu connecter screams low quality IMO
Click to expand...

But going back to my original question. I connected everything up. The worry was that I only have a 4 pin cpu power connector whereas the mb has a 8 pin socket. Switched on, and nothing. Everything dead. No leds, no fans. All I have is a white led on the gtx 1050 gpu.
Mb has been tested ok. Gpu has been working ok in another pc. I am told that my amd ryzen 5 2600 (no graphics) is ok with the tomahawk b450 mb.
Maybe it is the psu and its downmarket 4 pin cpu power plug. Any other ideas? How else can I test this?
 
ikcdab said:
Maybe it is the psu and its downmarket 4 pin cpu power plug.
Click to expand...

I'm not sure that there's any 'maybe' about it. It is the PSU. I'd bet all the money in the world on it. Either cremate it or bury it at sea, then go buy a proper one.
 
ikcdab said:
Why do you say it's a ticking time bomb? Is it not going to work or do you say it's going too blow up?
Click to expand...

It is a very low quality unit. The internals will have the cheapest components and the unit itself will be lacking most if not all protections (Current, Voltage and temperature etc). Units like this can fail in a big way and worse case scenario is that it takes all your other components with it.

I would suggest buying a better quality unit and sending that one back if you can. Buying a 4 pin to 8pin adapter is not a long term solution.
 
ikcdab said:
But going back to my original question. I connected everything up. The worry was that I only have a 4 pin cpu power connector whereas the mb has a 8 pin socket. Switched on, and nothing. Everything dead. No leds, no fans. All I have is a white led on the gtx 1050 gpu.
Mb has been tested ok. Gpu has been working ok in another pc. I am told that my amd ryzen 5 2600 (no graphics) is ok with the tomahawk b450 mb.
Maybe it is the psu and its downmarket 4 pin cpu power plug. Any other ideas? How else can I test this?
Click to expand...

You have been told correct it will work with your cpu, in the manual it makes no mention of a 4 pin being adequate so it needs an 8 pin plug, you probably could get an adapter but it's not worth the risk as if it blows it could take other components out with it.
Best bet is to test with a psu that has 8 pin (a friends?) or just buy a decent psu as you know the board has been tested.
 
Lordgrayone said:
You have been told correct it will work with your cpu, in the manual it makes no mention of a 4 pin being adequate so it needs an 8 pin plug, you probably could get an adapter but it's not worth the risk as if it blows it could take other components out with it.
Best bet is to test with a psu that has 8 pin (a friends?) or just buy a decent psu as you know the board has been tested.
Click to expand...

Thank you. About suggestions for a cost effective psu with the 8 pin cpu power supply suitable for the b450 tomahawk?
 
ikcdab said:
Thank you. About suggestions for a cost effective psu with the 8 pin cpu power supply suitable for the b450 tomahawk?
Click to expand...

Something as simple as this and dead cheap is 20 times more superior than the one you already have, and has 4+4 EPS connector for the CPU.

https://www.overclockers.co.uk/cougar-stx-550w-80-plus-230v-eu-power-supply-black-ca-018-cu.html

or even this, depends on your budget really:

https://www.overclockers.co.uk/supe...us-platinum-power-supply-black-ca-056-sf.html
 
Thanks for the replies and help. I've now ordered the Corsair CX 550m from Amazon. Good price too.
The MB and new PSU should all turn up tomorrow, so will be rebuilding it all then.
My plan is to assemble it on the bench first. MB, RAM, GPU, CPU, PSU and monitor. The switch on and see how it goes.
Will keep you posted.
 
Ok, so now I still need some help.
I have bought new CPU, Corsair cxm550. Motherboard has been returned from the retailer and I'm told they have tested it ok. Everyone tells me the mb and CPU are compatible.
I have bench assembled it.
Mb with GPU installed.
CPU and fan installed and plugged in.
PSU Installer. Power connected to mb, CPU and GPU.
Ram (Corsair ddr4 valueselect 8gb 2133mhz) seated.
Switch on psu. I see white led on gpu.
Short out power on pins.
No reaction at all. No fans, no ezdebug LEDs. Nothing. No beeps.
I can press the flashbios button on the mb and I see a red led flash, so I know power is reaching the mb.
What what can I do? Would not plugging in a ssd or case fan prevent booting?

Is it likely that the cpu is dead? But even of it is, why don't I see and ezdebug LEDs?

I'm really stuck now.

Thanks
 
You must log in or register to reply here.
Back
Top Bottom