HELP! Will this work or blow up right in my face?


Jul 31, 2008

Quick question: Will this PSU be enough for the rig below:

Gigabyte GA-EX58-UD4P
Core I7 920 Stock
Zalman 9500
12 Gb DDR3 OCZ 1066
2x BFG GTX 275
BFG 8800GT (Physx only)
2x Velociraptor 300 Gb RAID-0
2x Seagate 7200.10 500 Gb RAID-0
1x WD Caviar GP 1 Tb
1x Fujitsu Deskstar 500 Gb
1x DVD RW Pioneer
X-Fi Fatality Pro
Coolermaster CosmosS Full Tower w/ 4 120 mm fans...

PSU - BFG 800W 80+ SLI Cert, Active PFC (afaik, 64A combined on the 12V)

Right now I'm running it in the same system, but with only one GTX275. Apparently no issues regarding power... Computer online 24/7 for almost two weeks now without a single reboot, playing all sorts of games, video encoding, office, internet and all the usual stuff... I'm thinking about adding the second 275, but I'm not sure if the PSU will hold up or blow up.

If I have to change the PSU too, maybe I will Step-Up the GTX275 for one GTX295, assuming that one 295 would draw less power than 2 275 (and also that this would work...)

Could you please help me not having a time-bomb at home, just wating for that extra-click to explode?!





Jul 31, 2008

One more thing...

If I have to get a new PSU, what you guys would recommend?

I'm looking for something with good quality/brand, silent, modular (if possible) and not at an outrageous price....

I've hear good things about the HX1000, but I'm open to other suggestions...


May 28, 2009
You probably should up your PSU to a 1KW to be on the safe side.

Corsair 1000W HX series are the cream of the crop really, won too many awards to count.

IMO the second 275 isnt the issue, ill bet your main power draw comes from your HD's in RAID 0.

Still, the second 275 could be the straw that breaks the camels back. Be safe, invest in a bigger PSU and protect the rest of your machine from insufficient power.

That statement is so far from the truth I had to say something. HD's hardly use any power at all. A VelociRaptor, for example, uses 4.54W at idle and 6.52W under load.

I run 5 HD's in my system with a Corsair 520HX just fine. The new modular Corsair 850HX PSU is looking pretty good.

CORSAIR CMPSU-850HX 850W ATX12V 2.3 / EPS12V 2.91 Modular Active PFC Power Supply - Retail


Apr 24, 2008
My bet is that u wont have any problem. Two GTX295 and a 275 only get to roughly 700 watts.

Anyway if you really want a new psu get the antec Signature 850
here you can see the review

Just love their ripple suppresion and their stability, also see CP-850, if you can get it to fit in your case its equal to the signature but much cheaper,
the review

These two are the two best and most stable psu ive seen, allthough if u want to go to the 1k Watts psu go to the corsair HX, you wont need it but its also one of the best 1k watts psu.
Here u can see the review

And if you are wondering why do i recommend these antec before the corsair...... well because the corsair has a maximun theoritical of 60 Amps and the antecs have the signature 240 Amps and the cp 300Amps, sooo even though the wattage is less they are better builded, also theyr ripple and noise supression and voltage control is better.


Jul 31, 2008
Wow guys!

Thanks a bunch for the feedback! Really appreciated it.

Just a few more questions, since now you have shared with me more things to consider....

You're right that my PSU has only two PCIe 6 pin. That would feed one GTX 275, but I will have to use adaptors for the other one and the 8800GT... These adaptors uses two molex 4 pin for each 6 pin PCIe... That means that I will need 6 Molex 4 Pin to feed the whole thing, on the top of the two PCIe 6 pin...

There is no way that I will have 6 "independent" cables that I can put together to feed this whole thing. I will have to use two or more of each cable that I have in the PSU that has Molex connectors. Would that be of a problem or am I just being stupid?

Now, one other idea came to mind in the meantime. I just bought this GTX 275 a few weeks ago and I have 100 days before my BFG Step Up program expires. I payed 240$ on this GTX and, just as an example, one GTX295 in today's pricing is about 550$ or so. Let's say that Windows 7 comes within these 100 days left and, by chance nVidia comes with a new DirectX 11 card.

Even paying premium price on the new card just because they will be very fresh, most likely I would have to invest about 250-300$ to step up the GTX275 to the new one, assuming that a new card would come close to GTX 295 prices... And again theoretically I would not need to upgrade the PSU (which would save some $$)

If I buy now a new PSU around 200ish $, plus a new GTX275 at 250$ it will be significantly more than my step-up route described above...

I may be too much forward thinking here, but maybe you guys can share with me your thoughts.... What you guys think?

Thanks again for the help!


BTW, If anybody is considering a GTX275, please don't be afraid. The card is awesome! The only reason that I am thinking in another one is just because I am stupid enough to not settle down and enjoy what I already have.... I really need to control my spending habits, but this whole PC building thing is almost like drugs... (sorry for the poor example/joke)

I think stepping up to the gtx295 might be your best option.
It's performance will be somewhat like two GTX275 cards in sli, without the power issue.
It will run everything well.
Stepping up, you have to pay retail for the new card, but the GTX295 is not dropping in price, it seems to have a supply problem.
It may be that nvidia is planning to change the manufacturing on the card to put it all on one pcb.

I expect the next high end cards to show up nearer the end of the year.
Should you get the itch to get a new card then, I would think you could still get good value for a gtx295.