Why do people prefer discrete power supply units?

[Cerise Epiphany]

I have heard people say always go for a separate psu instead of the one built in the case. Why is it so?

[Moonzy]

if you mean the PSU that comes included with casings,

that's because they usually are of not good built quality

[BlueChinchillaEatingDorito]

8 minutes ago, Cerise Epiphany said:

I have heard people say always go for a separate psu instead of the one built in the case. Why is it so?

Most of these combos are on the low-end and are typically off-brand manufacturers. And such manufacturers never really have a good reputation of building safe and reliable PSUs. And even if you get a case + PSU combo from a reputable brand like Antec, it'll still be far from the best PSU for a "gaming rig". They might be ok for a basic office machine, but in terms of a expensive "gaming rig" which is what most people are building here, I would trust my investment with a better built PSU. 

 

Note: Also keep in mind, separate PSU doesn't always mean better. Still do your research on the PSU you're thinking of buying.  

[Cerise Epiphany]

What about asus tuf 650w bronze psu?

[Bombastinator]

To expand on this one can build a PSU that works for a while very cheaply.  The trick is building one that lasts a long time and fails (because they all eventually fail) in a manner that doesn’t take the whole rest of the computer with it.  That can be expensive.  A cheap PSU can destroy an entire machine when it fails.  The cables go literally everywhere. There was video of some PSUs actually catching fire when they failed, and doing so very soon after being installed.  There’s some really impressive video of a diablotek PSU going up for example.   When your $25 PSU destroys your $400 cpu people can get angry. 

[Cerise Epiphany]

3 minutes ago, Cerise Epiphany said:

What about asus tuf 650w bronze psu?

Is this a good one?

[Stahlmann]

Normally the included PSUs are of questionable quality. Sometimes they could even be classified as a fire hazard.

 

PSUs are usually only included in very low-budget cases. I've never seen a resonable quality case that comes with a PSU.

 

1 minute ago, Cerise Epiphany said:

What about asus tuf 650w bronze psu?

Is it THIS one? It's on the low-priority part of the PSU tier list: "Lack of info (no reviews) or minor issues (see the corresponding tab in the spreadsheet). Not recommended for purchase over any normal priority units."

[Bombastinator]

1 minute ago, Cerise Epiphany said:

Is this a good one?

The only info I got is the PSU tierlist. It I understand is made by folks who understand the ins and outs of how PSUs work a lot better than me.  I just look at the list.  It’s in the power supplies section iirc.

[Cerise Epiphany]

Can someone recommend a budget psu that won't destroy my machine?

[mariushm]

Because power supplies in cases are most of the time seen as a way to increase the profit per unit (case) sold, to sell more cases, not to give end user value and quality. They're not as quality as separate power supplies. 

 

Majority of people that want cases with power supplies look to save money by buying these two together - if they can buy a power supply separately and get the same price, they will.

But, a case manufacturer most likely doesn't have the ordering power to get huge discounts on OEM power supplies, so they don't get the power supplies as cheap as others.

So, the case manufacturer will try to cut corners somewhere (use bronze efficiency psu, use  shorter cables, use cables without sleeving, use fewer connectors, use cheaper fan on the power supply

Also, they'll often cut cost by removing components from power supplies like input filtering, because such cases are often sold in regions where laws are less strict or nobody cares to check the internals (Russia, Brazil, etc)  

 

Keep in mind the warranty of the power supply that comes with the case is often as long as the case itself, usually 2-3 years. In comparison companies like Seasonic offer up to 12 years of warranty for their power supplies. 

And if the power supply does fail, think how easy it would be to have it replaced, will you pull out your components to send the case back with the power supply?