• Competitor rules

    Please remember that any mention of competitors, hinting at competitors or offering to provide details of competitors will result in an account suspension. The full rules can be found under the 'Terms and Rules' link in the bottom right corner of your screen. Just don't mention competitors in any way, shape or form and you'll be OK.

What PSU for a 290x?

Which OCZ unit do you have? Just because it says 550w in big text on the side doesn't mean it can deliver 550w on the 12v rail where it counts. A lot of the OCZ units had weak rails. The Fatality 550w had 450/495w (depending on the version) on the 12v rail while the ZS550w only had 456w. PSU's are not all equal and for the most part the total capacity should be ignored and actually look up what a psu is actually capable of.
 
Last edited:
Bonjour said:
I wouldn't trust a 290X to an aged OCZ 550W PSU.

550W is fine if you have a recent, Gold 90+ single 12V rail power supply.
Click to expand...

Used my MSi R9 290X Lightning with overclock (1100/1600 for 24/7 if I remember correctly what it was before I upgraded and +100mV on the core) with an overclocked Ivy Bridge i5 processor on a Corsair HX520 for about two weeks. I upgraded to the power supply in my signature - Fractal Edison M 750W (Seasonic G-750 OEM) and the difference is, well you guessed it - 0. :) Even in the bench results there is 0 effect of a more powerful power supply. If you don't have a socket 2011 or AM3+ FX processor, ~500W quality PSU is sufficient if you do not plan to do extreme overclocking at >+100mV.
 
Last edited:
Stuen4y said:
Used my MSi R9 290X Lightning with overclock (1100/1600 for 24/7 if I remember correctly what it was before I upgraded and +100mV on the core) with an overclocked Ivy Bridge i5 processor on a Corsair HX520 for about two weeks. I upgraded to the power supply in my signature - Fractal Edison M 750W (Seasonic G-750 OEM) and the difference is, well you guessed it - 0. :) Even in the bench results there is 0 effect of a more powerful power supply. If you don't have a socket 2011 or AM3+ FX processor, ~500W quality PSU is sufficient if you do not plan to do extreme overclocking at >+100mV.
Click to expand...
The difference is that the HX520 can probably deliver about 500W+ on the 12v rail, while the OCZ 550W as others have pointed is only 38A and only be able to do like 456W on the 12v rail.
 
RJC said:
A 550w will be fine - Your current psu should be ok for gaming.

I think I got 500w odd with my MSI LE and a Overclocked 4770k, I did run Furmark and prime together.
Click to expand...

No OC involve I guess?
I've 1220/1750 hd 7970( 1,21 and 1,3V) and I run Furmark benchmark(1080p),and I trip my psu,reading on the meter was 940W.(no prime 95)
In games highest I've seen was 750W(pull from the wall),Sleeping Dogs on max settings,other games use less than that(Metro Last Night Redux,Tomb Raider) around 650W.
Valley benchmark=670W,Heaven Benchmark less than 600W
In games even with OC I never going above psu power limit.
Furmark and OC= silly amount of power used in scenario which never going to happen in really gaming
 
That was with the default overclocked speeds, as you mentioned Furmark and Prime will always be way over the top.
 
People need to realise with Furmark and prime95 it's stressing all your system to 100% constantly without a breath which is why you get ridiculous power readings. In real world usage even in games your system will never run 100% either your GPU or CPU will not be running at full speed as well as your RAM(don't really mean speed with ram but prime95 does stress the ram beyond real world usage).

Games are never that well optimized that it will utilise systems like that and there is always some sort of bottleneck be it the cpu or GPU grunt. Thats why you should never take 100% readings always knock at least 10% off for a more accurate reading.
 
I can remember running furmark and p95 small fft simultaneously on my old 4.2ghz i7 920 with sli gtx 470's. Corsair hx850w psu, straight of the bat my power metre was showing 860w. I stopped it pretty quickly. Now people say that amd 290's like a bit of juice, being more modern cards they got nothing on an nv 400 series. But they were the best clocking cards ive ever owned. 850mhz core with a very small v increase. Which nvidia wont let you do now, spoil sports.:o
 
Stuen4y said:
Used my MSi R9 290X Lightning with overclock (1100/1600 for 24/7 if I remember correctly what it was before I upgraded and +100mV on the core) with an overclocked Ivy Bridge i5 processor on a Corsair HX520 for about two weeks. I upgraded to the power supply in my signature - Fractal Edison M 750W (Seasonic G-750 OEM) and the difference is, well you guessed it - 0. :) Even in the bench results there is 0 effect of a more powerful power supply. If you don't have a socket 2011 or AM3+ FX processor, ~500W quality PSU is sufficient if you do not plan to do extreme overclocking at >+100mV.
Click to expand...

A better power supply is not about getting higher benchmark scores (really?), it's about using your computer in relative confidence the PSU isn't about to expire and take one or more of your components with it.

I have experience of an OCZ (Fatal1ty) PSU going in a system that was well under its rated power, and taking the mobo and GPU with it.
 
This is the PSU I have now - OCZ-ZS550W-UK. That is the model number. I would link but it seems to be a competitors site.

The main thing I don't like about this PSU is that is has only 1 PCI-e connector so I have to power the other one using a 4 pin molex. Would this effect performance any?
 
I wouldn't use it then, if its not supplied with the correct leads then in my view its not meant to be used for it.
 
I wouldn't use a Molex adapter for such a high end GPU, the Molex rails are for Drives, 10 / 20 Watt units, they are not designed to carry 75 Watts, the cables might not be made of the sterner stuff.
 
Last edited:
Would there be anything I can get for around the £50 region or would I have to spend about £70? Really don't want to go past £70.
 
Tom_D said:
This is the PSU I have now - OCZ-ZS550W-UK. That is the model number. I would link but it seems to be a competitors site.

The main thing I don't like about this PSU is that is has only 1 PCI-e connector so I have to power the other one using a 4 pin molex. Would this effect performance any?
Click to expand...


Like I posted yesterday, you only have 456w on the 12v rails so you need a new psu. It doesn't matter that your psu has a big sticker saying 550w, it can't deliver that on the 12v rails where it's needed. Ignore the sticker and look up what a psu is actually capable of. This is a excellent resource for psu information and reviews. The Superflower Golden Green HX550 is a vastly superior psu than your OCZ and has 546w on the single 12v rail and is the best you are going to get for £50. Personally I would want 650w for a 290X just for the extra headroom.
 
Last edited:
You must log in or register to reply here.
Back
Top Bottom