Another Corsair CX-series PSU victim.

Before I go to Corsair on this, I'd just like some opinions. This PSU was given to me a few months ago as a gift, and I have the store receipt and registered it immediately with Corsair. I installed it in my old 2500K/680SLI gaming PC (see sig below) after the 5-year old TX750 for it died. This backup PC doesn't get much time in use anymore, so the PSU at best probably only has about 50 hours on it.

It had been running fine, but a couple of weeks ago I started getting random crashes in games under load. The +12v variation shows well within ATX tolerance (12.192v max, 12.000v min showing in HWMonitor), so it's not faulty from that aspect. Then I decided to finally disable one of the 680s and see what happens. No crashes. I installed the Corsair RM850i from my primary rig and reconnected SLI and no crashes.

So the PSU technically works fine and the 62A on the +12v rail well cover's Nvidia's minimum 53A requirement for 680SLI. But the CX750M is apparently not capable of sustaining power like a 750W PSU should when under a higher load. I'm technically at the minimum 750W rating by Nvidia but the +12A rating is fine. I don't think the PSU is faulty, just crappy and not fully capable of producing the power shown on paper that it should (just like Johnny's review of it says).

How should I approach this with Corsair?
 
Solution
That is the nature of low quality PSUs (or anything else for that matter - think of the 1970's Fiat autos sold in the US). They work fine for a while and then they don't. How long will it work fine ? Luck of the draw. Those cheap Chinese made capacitors just don't hold up. I have replaced capacitors in 1 TV power supply and 2 computer monitor's power supplies in the last couple of years and they are still going strong. However it is just not worth replacing them in a PSU, because they probably also used thin-gauge wire also, and you would end up rebuilding the whole thing. Plus, it is kind of dangerous if you don't fully know what you are doing.


Yeah I thought of that but my case has excellent airflow and internal temps are only about 4-5C above ambient (about 20-22 average) with a thermal laser zapper. I just wonder if Corsair gets it and they find nothing "wrong" with it they can reject my claim....after I spend my own money to RMA ship it.

 
My "guess" is Corsair will not give you a replacement (why would you even want another CX anyway) if you try to RMA it. If it is not fully capable of producing the power shown on paper that it should, is not a warranty issue, it is more of a legal issue. False advertising or something along those lines.
 


^^That's what I'm afraid of. It didn't cost me anything, but there is still a chance something is failing since it worked fine for a while powering SLI and temps have not changed much indoors (specifically inside my case). Unfortunately I do not have a PSU tester nor know someone with one. It's a roll of the dice.
 
That is the nature of low quality PSUs (or anything else for that matter - think of the 1970's Fiat autos sold in the US). They work fine for a while and then they don't. How long will it work fine ? Luck of the draw. Those cheap Chinese made capacitors just don't hold up. I have replaced capacitors in 1 TV power supply and 2 computer monitor's power supplies in the last couple of years and they are still going strong. However it is just not worth replacing them in a PSU, because they probably also used thin-gauge wire also, and you would end up rebuilding the whole thing. Plus, it is kind of dangerous if you don't fully know what you are doing.
 
Solution