Please help with Power Supply Requirement

[Inbox4]

Hi,

Could I please have comments on power supply requirements and whether my existing PS is sufficient if I were to upgrade my graphics card?

My system currently has a Corsair RMx 750w PS
My PC Specialist order shows a current Maximum Required Power of 693W

I currently have a Sapphire Nitro 5700XT card. The power consumption on Sapphire’s web site shows as 265W. The card I am interested in (RX6800XT) has a power consumption of 300W.

300W is 35W more than my current card. Does this therefore mean that my new power requirement is 728W which is within the 750W my current PS provides?

Does this mean my current PS is fine or do I need extra headroom?

(I have added an additional SSD and doubled the RAM since the 693W figure was provided. I do not know the consumption of either. Is this a significant consideration?)

Many thanks for any advice or clarification.

 

[BlessedSquirrel]

Yes, you’d want a minimum of 850w for the new configuration. You always want about 100w headroom, it’s not a good idea to fully load a PSU.

 

[Inbox4]

Yes, you’d want a minimum of 850w for the new configuration. You always want about 100w headroom, it’s not a good idea to fully load a PSU.

Thanks very much for your reply.

AMD recommend a 750w power supply for the new 300w RX6800xt.

Are you suggesting my system is unusually power hungry if my 750w power supply is insufficient and I require more than is recommended?

Many thanks.

 

[BlessedSquirrel]

Thanks very much for your reply.

AMD recommend a 750w power supply for the new 300w RX6800xt.

Are you suggesting my system is unusually power hungry if my 750w power supply is insufficient and I require more than is recommended?

Many thanks.

The recommended PSU is never normally what you'd select, always allow yourself some headroom.

You don't have to match a PSU to the requirements, in fact that's exactly what not to do. So long as you've got enough, you normally overspec to allow for 100W headroom.

 

[Inbox4]

The recommended PSU is never normally what you'd select, always allow yourself some headroom.

You don't have to match a PSU to the requirements, in fact that's exactly what not to do. So long as you've got enough, you normally overspec to allow for 100W headroom.

Based on your advice about my power supply not being sufficient for the graphics card, I'm thinking of upgrading to a 1000w model.

I have three questions:

1) I know this is overkill for my system and the new cards. However, a decent PSU should last for many years and a 1000w should give enough headroom to make any future upgrades for many tech generations without me needing to give any consideration to the power supply. Are there any reasons not to take this approach?

2) Am I able to disconnect my RM750x PSU and slot a new PSU in its place and use my existing cables? PC Specialist need a very nice, neat job when building my PC. I would rather not re-wire it myself with the new cables that come with the new PSU.

3) Is it possible to make mistakes when connecting a PSU or will it work as longer as the connector fits the socket on the PSU?

Thanks again for any advice.

 

[BlessedSquirrel]

1. No harm in getting much higher W than required, usually it’s a better tier of PSU in build quality so is often worth going to for the better class of electronics. The system will only use what it needs no matter the rating of the PSU.

2. No, you would need to swap out the cables for the ones that came with the new PSU.

PSA: Mixing Modular PSU Cables Can Kill Components

Mixing cables between power supplies can kill them or kill attached components. Not always, but it can -- and when the wiring crosses in exactly the wrong way, the failure will be spectacular. -

www.gamersnexus.net

3. Very difficult. Connectors only fit their dedicated slots on motherboard. PSU ports are labelled also.

 

[Inbox4]

1. No harm in getting much higher W than required, usually it’s a better tier of PSU in build quality so is often worth going to for the better class of electronics. The system will only use what it needs no matter the rating of the PSU.

2. No, you would need to swap out the cables for the ones that came with the new PSU.

PSA: Mixing Modular PSU Cables Can Kill Components

Mixing cables between power supplies can kill them or kill attached components. Not always, but it can -- and when the wiring crosses in exactly the wrong way, the failure will be spectacular. -

www.gamersnexus.net

3. Very difficult. Connectors only fit their dedicated slots on motherboard. PSU ports are labelled also.

Thanks, very useful.

Would you also recommend against keeping my existing cables if I stick to the same brand of PSU? I've asked Corsair but I haven't managed to get any sense out of them so far.

 

[BlessedSquirrel]

Thanks, very useful.

Would you also recommend against keeping my existing cables if I stick to the same brand of PSU? I've asked Corsair but I haven't managed to get any sense out of them so far.

Yeah, any new PSU you need to use the cables supplied.