Need help with new power supply purchase

[Thomaszee]

Hey there I'm going to upgrade my power supply of 400W to 700W+, but I'm not sure if it will be compatible with my current hardware.

Current hardware:

Graphics card: NVIDIA GeForce GTX 550 Ti
CPU: AMD Athlon II x4 620
RAM: 6GB Dual-Channel DDR2 @399MHz
Motherboard: Acer RS780HVF (AM2)
Hard Drives: 699GB Western Digital WDC WD7501AALS-00J7B1 ATA Device (SATA) [x2]

Speccy Spec snapshot: http://speccy.piriform.com/results/5cSkReG2qAH7lPclRqaxxWP
Thanks in advance

 

[Apprentrice5]

Hi Thomaszee, im not an expert on PSU's but i have a 650w PSU in my machine and there is no problem there, and from what i can see from your spec you shouldnt have a problem with a 700w+, just make sure you purchase from a decent manufacturer.

Also if i am right in thinking (correct me if im wrong) also gotta look at the 12v rail? to make sure there will be enough power to the GPU??

Also to save writing out your system spec for each post, update your system spec

Hope it helps

Regards
Toby

 

[Thomaszee]

I'm planning on buying a corsair PSU, most of them have a 12v rail so should be fine on that

 

[TVeblen]

You can use this tool:
eXtreme Power Supply Calculator
to calculate what you need.

Don't forget to fill in the last box: Capacitor Aging. This compensates for the known loss in power that happens as your power supply gets older. The general rule of thumb is to enter 10% for each year you expect to use the supply in your system.

 

[bobkn]

eVGA recommends a power supply with at least 400W and 24A at +12V for their 550ti card.

Aside from that, your graphics card needs a PCI-E 6 pin auxiliary power connector. (A Molex-to-PCI-E adapter would be an alternative, but it's best to not use adapters.) It needs a 24 pin pin ATX power connector. (20+4 would be fine.) It also needs a 4 pin ATX 12V power connector for the CPU.

Why are you upgrading the PSU? If you have a good 400W one, it's adequate. It would make sense to put a higher powered graphics card in this oldish PC.

If you have the money, it might make sense to buy a larger capacity PSU that can follow you through future upgrades. My old PC Power & Cooling Silencer 750 has lived in several cases. Its electrolytic capacitors haven't shown any tendency to die yet.

 

[Thomaszee]

Well, the graphics card requires 500W on itself (recommendation on nvidia website) and it also has to feed all other components.

 

[stormy13]

No the card doesn't require 500W itself. That 500W that video card manufacturer's recommend is for the system total, and is always higher than actually needed to take into account people using low quality no name power supplies.

This,

ASUS GeForce GTX 550 Ti Direct CU 1 GB Review | techPowerUp

will give you an idea of what the card actually uses.

 

[AddRAM]

A Corsair 700 will be more than adequate. Which model were you thinking of getting ?

http://www.newegg.com/Product/Product.aspx?Item=N82E16817139010

http://www.tigerdirect.com/applications/Category/guidedSearch.asp?CatId=106&sel=Mfr%3BMfr_1499,Detail%3B145_435_37813_51107

http://www.newegg.com/Power-Supplies/Category/ID-32

Just for research purposes, not sure if they ship to you.

My new one will be the HX750

 

[Thomaszee]

A Corsair 700 will be more than adequate. Which model were you thinking of getting ?

CORSAIR HX Series HX750 750W ATX12V 2.3 / EPS12V 2.91 SLI Ready CrossFire Ready 80 PLUS GOLD Certified Modular Active PFC Power Supply - Newegg.com

Corsair Power Supplies 700W - 999W Wattage at TigerDirect.com

Power Supplies - Newegg.com

Just for research purposes, not sure if they ship to you.

My new one will be the HX750

Still deciding on which to buy but that one does look good indeed

 

[AddRAM]

For $10 more you could get the AX. You`d have to research what the difference is.

CORSAIR Professional Series Gold AX750 (CMPSU-750AX) 750W ATX12V v2.31 / EPS12V v2.92 80 PLUS GOLD Certified Modular Active PFC Power Supply - Newegg.com

 

[Layback Bear]

Corsair Gold or better would be very good now and for use in the future.
Modular would even be nicer.
Check the price difference between a 700 or 750W and a 850W. Sometimes with sales their is very little difference. Their is no such thing as to much power.

 

[bobkn]

No the card doesn't require 500W itself. That 500W that video card manufacturer's recommend is for the system total, and is always higher than actually needed to take into account people using low quality no name power supplies.

This,

ASUS GeForce GTX 550 Ti Direct CU 1 GB Review | techPowerUp

will give you an idea of what the card actually uses.

Right.

The Asus card comes very close to the 150W nominal limit for a PCI-E card with a single 6 pin auxiliary connector.

Actually, the eVGA requirement is surprisingly low. Not so much the total power as the +12V current. However, a PSU like a Corsair CX430, while only a nominal 430W PSU, is rated at 32A at +12V. That would be more than adequate for your current system. I'd recommend going to a larger capacity, though, mainly because the price increase would probably be small.

The Corsair HX750 is about twice the PSU you'd need with your current PC. Overkill, unless you're buying it to move to a monster system later. Why not an AX1200? That's be triple what you'd need. It wouldn't be quite enough to handle four Radeon HD 7970s in Crossfire, but one must make small economies.

(Sorry. Got a bit carried away. Sometimes I think I've stumbled into a PSU fetishist site.)

 

[Erick Aguilar]

Corsair Gold or better would be very good now and for use in the future.
Modular would even be nicer.
Check the price difference between a 700 or 750W and a 850W. Sometimes with sales their is very little difference. Their is no such thing as to much power.

I believe I heard something about a PSU being bottlenecked and not achieving it's full efficency if you give it a system which doesn't get close it's peak wattage.

 

[bobkn]

Corsair Gold or better would be very good now and for use in the future.
Modular would even be nicer.
Check the price difference between a 700 or 750W and a 850W. Sometimes with sales their is very little difference. Their is no such thing as to much power.

I believe I heard something about a PSU being bottlenecked and not achieving it's full efficency if you give it a system which doesn't get close it's peak wattage.

80 Plus - Wikipedia, the free encyclopedia

An 80+ Gold certified PSU is above 87% efficiency at 20% and 100% of its rated power, with a higher efficiency within that range. If true, there's no issue.

 

[Layback Bear]

Every power supply has its sweet spot but a bottle neck. Never heard of such a thing.