Need for a new PSU or not...

flinco

flinco

flinco

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Hi all,

I have recently secured a 2nd hand GTX 780 Hall of Fame as an upgrade to my GTX 670.

Currently I am running the 670 and my i5 750 @ 4.1Ghz @ 1.375 ish V on a 3 year old BeQuiet L7 530w PSU.

This has twin 12v rails of 22 amps each, with the 780 requiring 42 amps. However from the two reviews I've read of the HOF version, it seems to use between 70-90w more than a Titan.

I'm worried that when I install this 15% factory overclocked 780 that I will no longer be very stable when gaming.

In an attempt to alleviate the situation prior to recieving the card, I am in the process of finding the lowest possible voltage for a stable 4 Ghz overclock. Currently benching OCCT @ 1.33v.

I don't really want to buy a new PSU, but I suppose I'll find out when the 780 arrives. Is there any danger in pushing the PSU to the limit? I would have thought it would shut of in the event the power draw was too high to satisfy.

Any thoughts gents?
 
TTL has just done a video on this very subject with a i5 and a 780 Ti running off a Corsair 450 Watt PSU, max draw was 430 ish.

Not sure if this helps with your situation, but is may give you a pointer.
 
Your psu only has 420w on the 12v rails so i would replace it with a quality one that can actually deliver what it's supposed to on the all important 12v rail. Find a psu that you are interested in and then look here to see what it can actually deliver. The site is regularly updated and has details such as who the OEM is, power on the 12v rail, single or multiple 12v rails, plus links to reviews. I have made my pc pull 521w from the wall by running Furmark and linx together, 432w just from running Furmark, 267w just by running linx. Normal gaming is anything between 350-480w (at the wall, so the psu will be delivering a bit less to the pc) depending on the game. Have a look for a decent 600w psu from the likes of Seasonic, Enermax, Antec and Superflower.
 
I appreciate I probably need to get a new PSU. I was looking at this one:

SuperFlower Leadex GOLD 650W Fully Modular "80 Plus Gold" Power Supply

http://www.overclockers.co.uk/showproduct.php?prodid=CA-014-SF&groupid=701&catid=123&subcat=2057

There are a few reasons I don't want to buy one though:

1) I believe I may be able to run the system with the current PSU and the 780 assuming I don't overclock the 780 and significantly reduce my CPU overclock.

2) If i get the new PSU this gives me the extra power to be able to retain my 4.1 ghz OC and allow me to OC the 780. However my current case and its cooling capabilities would have no chance with an extra 150-200w of heat than it currently produces. This would require an extra £80 + for a new case and £89 for the PSU.

With option 2 I go from a simple £100 upgrade (£235 minus ~£135 from selling my 670) to a £270 upgrade!

Its likely I will end up getting a new PSU at least. But firstly I want to try the 780 with my current PSU. I'm worried that this may cause damage.

Is it likely that I will just suffer instability or power cut outs, or does anyone believe there's a serious risk to the health of my components?
 
CEUOTC said:
TTL has just done a video on this very subject with a i5 and a 780 Ti running off a Corsair 450 Watt PSU, max draw was 430 ish.

Not sure if this helps with your situation, but is may give you a pointer.
Click to expand...

Thanks, that was an interesting video. Looks like my PSU may cope assuming I keep the OC's low.
 
pastymuncher said:
Your psu only has 420w on the 12v rails so i would replace it with a quality one that can actually deliver what it's supposed to on the all important 12v rail. Find a psu that you are interested in and then look here to see what it can actually deliver. The site is regularly updated and has details such as who the OEM is, power on the 12v rail, single or multiple 12v rails, plus links to reviews. I have made my pc pull 521w from the wall by running Furmark and linx together, 432w just from running Furmark, 267w just by running linx. Normal gaming is anything between 350-480w (at the wall, so the psu will be delivering a bit less to the pc) depending on the game. Have a look for a decent 600w psu from the likes of Seasonic, Enermax, Antec and Superflower.
Click to expand...

Are these power figures with your 780 OC'd? From my research it seems overclocking these cards massively increases their power consumption.

When it arrives, I'll set the CPU to stock and do some GPU benching. It should cope perfectly well like that.
 
Not clocked. It's running at stock clocks on bios 1 with the lower power limit. Your card will pull more power than mine too. Previously i had a i5 760 clocked at 4ghz with 1.275v along with a Palit GTX670 Jetstream and that rig would also draw more than 400w. I really wouldn't be comfortable running what you intend to run on that psu. At the end of the day it's just a budget psu.
 
You're probably right. I'll order the Superflower 650 watter then. Its a shame, I just spent 3 quid on a 6 to 8 pin pcie adapter. Guess I can send it back!
 
It will cost at least half that to send it back. Keep it as a spare or flog it on the bay. The prices people pay for stuff on there you could probably sell it for a tenner and still be quids in after fee's. :D

Which superflower, Golden green or the Leadex? Personally i would pay the extra tenner for the Leadex as it's fully modular. Might be worth checking the weekly deals when they update tomorrow before ordering anything.
 
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Was going to go for the Leadex. As you say, it's definitely worth an extra tenner to go modular, especially when you have a cramped case like my Antec 300.

Good shout on waiting for the deals to update, will wait till then.
 
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