Power Supply Unit (PSU) help needed

Man, I think it’s finally time to swap out my power supply.

Here’s what’s currently running in my rig:

Intel(R)Core(TM)2 Duo CPU E7200 @2.53 GHz 2.53 GHz
RAM: 4.00 GB (3.5 used), type: DDR2
Motherboard: ASUSTeK Computer INC., model: P5KPL
GPU: NVIDIA GeForce GT 540

I found a few options that look okay, so I wanted to run them by you guys—tell me if they actually work for this setup and rank them from best to worst, please.

1. PSU 460W
One 24-pin connector, one 20-pin connector, 3 SATA, 1x 4-pin Molex

2. EZ COOL 500W
Power: 500W, includes an 80mm fan, Connectors: 24-pin ATX, 2x 4-pin Molex, 2x SATA

3. Spire 500W
Power: 500W, includes an 80mm fan, Connectors: 24-pin ATX, 2x 4-pin Molex, 2x SATA, 1x Floppy

Those are all just bottom-tier power supplies, and honestly, they’re pretty much all the same. For starters, there isn't even a specific model or brand listed, so we're basically flying blind. Between Spira and EZ cool, I guess EZ cool looks better on paper, but those specs are usually just stickers. They always lie about those cheap units, claiming some peak wattage they can only hold for maybe ten seconds before dying. 😬

My advice is to stay far away from these budget units, but since the PC is old, I suppose it'll do its job for a bit. Just make sure it's at least new...

fadedorca66 said:Look, we're talking about bottom-of-the-barrel power supplies here—they're all basically the same junk. First off, there’s no actual model or brand listed, so we're flying blind. Even if you compare Spira to EZ cool, EZ cool looks better on paper, but honestly? That's just a sticker. Those cheap units always lie about their specs—they'll claim some massive wattage that they can only hold for maybe ten seconds before dying. It's all a scam. 😬

My advice? Stay far away from those budget units. But hey, since the PC is old anyway, I guess it'll do the job for a bit. Just make sure whatever you grab is actually new...

Thanks.👍

What do you think about this PSU down here?

It's some random Chinese unit I found via a QR code online, but the whole description is in Chinese.

You might as well play it safe and grab an Office Series LC POWER LC420-12 V2.31, 350 W, 120 mm, 80+ Bronze.

Can I use either one of these, and which one is actually better—the first or the second?

1. LC-Power 500W power supply, LC500H-12
Power: 500W. Fan size: 120 mm. Connectors: ATX V2.2, 20 + 4 Pin, 4+4 Pin, 4x SATA, 2x PATA, 1x Floppy.

2. LC-Power 500W power supply, LC500-12
Power: 500W. Fan size: 120mm. Connectors: ATX V2.31, 20+4 Pin, 4+4 pin 12V, 4x SATA, 2x PATA and 1x Floppy. 80+ certified.

The second option works fine

Thanks 👍

Can someone explain why my PC only works if I plug it in one specific way? It’s like the plug has to go "uphill" into the outlet just to function...

Just a heads up—if I flip it 180 degrees, it immediately trips the circuit breaker...

To rule out the outlet, try plugging in something simple like a hair straightener or a kitchen mixer to see if they actually get power in both positions.
If you want to test the PC power cord, just swap it out for a different one and see if that fixes the issue.
If nothing changes, then we’re looking at something deeper. You'll need to pull the power supply unit and check the capacitors on the 120V input side—those act as filters along with the dual choke before the bridge rectifier/diodes. There's a chance one of those caps has shorted out to ground.

It’s just the power supply—it works on any outlet as long as I plug it in one specific way. Flip the orientation, and the breaker trips immediately. Tried swapping the cable already... same result, so it isn't the cord.

Since tracking down a replacement with the right isolation specs is a massive pain right now, I'm wondering how risky it actually is to keep using a unit like this? What kind of damage am I looking at here?

Fixing the power supply myself seems a bit out of my league...

Sarah Patel66 said:It’s purely the power supply itself; it works fine in every outlet, provided I plug it in one specific way. The moment I flip the orientation, the circuit breaker trips. I already tried swapping out the cord, but the result was identical—so it isn't the cable.

Since finding a replacement power supply with the same isolation specs is such a hassle right now, I find myself wondering just how dangerous it is to keep using this unit. What kind of risks am I actually looking at here?

I suspect repairing the power supply would be far too complex for my skill set.

It isn't. You simply need to clip out the blown capacitor. Post a photo and I will point out which one it is.

Jerry Robinson56 said:Nah, you just need to clip out the "blown" capacitor. Post a photo and I'll point out which one it is.

The unit in question is a Corsair RM series gold 550W—it’s under a 5-year warranty and finally gave up the ghost. Since the warranty is still active, the plan is to send it in for an RMA and just get a fresh replacement.

In the meantime, I'm running a borrowed EVGA SuperNOVA 1200 W. from a buddy.

I figure the easiest move is to just leave this loaner in place until my original unit comes back from service... then, if things go south or I run into issues, maybe I'll try fixing the old one by removing that capacitor.

Just to confirm though—using this current setup (which only works when plugged in a very specific way) isn't going to cause any damage, right?

Thanks for the help, everyone.