Corsair HX520 and SLI

Hi

 

Never bothered with SLI before, but thinking of it now due to a good deal on some 7950GT cards.

 

According to the site, I ''should' be able to use the 520 to power up two 7950GT's in SLI mode.

 

However, does this mean the PSU 'can' do it, and or does it mean it will do it no problem? The former means that the system would be under pressure all the time, the latter no worries about a strain on the system at all.

 

Can anyone hazard a guess at which it is?

 

Cheers

Hi

 

Thanks for the input.

 

However, I installed the second 7950GT and all was not good. Never mind the system problems (mouse behaving erratically etc), the PSU was so stressed it was making the case resonate at an unpleasant pitch and level.

 

This was all without even running a game!

 

I couldn't handle the noise the PSU/case was making so I powered down, pulled the 2nd card, and switched off.

 

The noise levels then settled. But, I then pulled the single 7950Gt and put back the 7800GT it recently replaced.

 

Noise right back down to sensible levels, pre installing even the single 7950GT, all system problems gone.

 

Now, is there a problem with PSU? Bearing in mind it struggled even with a single 7950GT in my system. The spec of which isn't impressive as you can see.

 

Please let me know what you think?

The Corsair Hx520 should easily power 7950GT in SLI. Powers my two 4850s fine. Can you test both cards to make sure it's not one of the cards?

Hi

 

Tried both cards, same results. I also tried them in a different PC and there was no problem there.

 

The reason I had two in the first place, was because I was getting higher than expected noise levels from the PSU when I installed the first one, and because the system took a performance hit overall, with 'odd' things happening. Hence the supplier sent me a second to test.

 

There was no difference with either card. The chances of both being failures is minimal.

 

I tried both cards at once to see if it would reveal that the problem might lie with PSU rather than a compatibility problem with the OS. When the PSU started producing steam engine like levels of noise I deemed it wise to hit the off button!

 

Another odd thing happened as well. I suspect a surge on one of the lines, as both (at once) of the Wavemasters front LED's have blown while all this was going on. Now, one might fail, even though they are expected to outlive the case, but two? Luckily only the lights and fans are on that line. Fans are too tough for anything but a really big surge to damage.

 

Still worrying though.

 

Was hoping Ramguy would come back with some advise.

Can you describe the noise again?

 

How are you determining the source of the sound you are hearing. I have seen problems like this where users hear the sound out the back of the PSU but it is actually coming from inside the case, usually the MOBO.

 

Also, I am assuming that you plugged in the secondary PCI-e cable to each video card?

Hi

 

The noise is caused by vibration, coming from the PSU. The vibrations can be traced back to the unit (by touch, never mind sound), and there are no fans on the mobo bar the CPU, and I can assure you, it wasn't that. Even with both the VGA cards fans running flat out they could not have produced that level of noise.

 

The vibration noise is also still there, just significantly quieter now the 7800GT has been restored.

 

The vibrations also aren't coming from the centre of the case, but running along the top from back to front.

 

When the noise was at it's worst I had both side panels off, if that gives any indication of how bad the resonance was.

 

Hope that helps.

It sounds like you have a unit that either

A: has an obstruction in the fan or

B: has a defective fan

 

In either case, we'll replace the unit and we're sorry you had the issue. Use the link below in my signature for TSX Express to start your RMA.

Hi

 

Thanks for that SpecMike. That explains both problems. If it's running 'rough' it will create vibration, and if it's struggling to get to the required speed to cool the unit when its under pressure, that would explain why the system was not performing right.

 

I should add I'm a UK customer.

 

I cannot find the receipt/invoice for it either! Which, with the amount of ludicrous receipts I still have for that PC (for the Sharkoon fans no less!) is ridiculous.

 

Is that going to cause a problem?

 

Obviously you check the build and dispatch to the retailer dates from the serial number, but will I need to supply that first?

Only if they ask for it, which isn't often.

Thanks.

 

It's been a real eye opener using Corsairs Support forum.

 

I've been using the products for years and never needed too (which is a good advert in itself) use it, but when you do and everyone tries to help in such a positive manner it's great!

 

I speak from having worked on support forums myself, and from having had to use others in the past............ no names here! :roll:

 

Thanks again, all!

If you have the option, it may be faster and/or less expensive on shipping to RMA to your vendor as our RMA facility for the UK is in the Netherlands.

 

If you misplaced your receipt, we do not require it. However, your vendor should have a copy available if you bought online.

If you have the option, it may be faster and/or less expensive on shipping to RMA to your vendor as our RMA facility for the UK is in the Netherlands.

 

If you misplaced your receipt, we do not require it. However, your vendor should have a copy available if you bought online.

Tbh I'm racking my brains to remember who it was! I usually only buy from three online sources. However, I have on occasion bought, as a result of particularly good price, one off items from elsewhere.

 

With the main vendors I have no problem as I just go through my order history until I find when the item was bought. If it's a one off...............:ummmm:

 

Unfortunately, in this case I suspect the latter. :roll:

Hi all

 

I sent the PSU to Corsair, and they sent me a replacement within a few days of testing. I have to say that is excellent service considering it was overseas postage!

 

I would just like to thank everyone on here for their help and advice, and Corsair for their prompt and effective RMA system.

 

Happy Xmas to all, and best wishes for the New year.

 

Overkill2