PC Power supply question

[patchoo78]

I have an old PC that was given, I have just plugged it in and the power supply blew up...

I have 3 spare but I'm a bit confused about Voltage and Wattage..

The power supply that blew up was 400 watts, one of the power supplies I have is 430 Watts.

2.8ghz CPU

2 Hard drives

CD/RW

Running Windows XP

Is it safe to put the 430 Watt power supply in the PC? 

[cq_tech]

Yes Patch, it's perfectly safe, and will probably even run slightly cooler than your previous 400W PSU. A general rule of thumb is that it's perfectly OK to change to a higher-rated power supply, but definitely not the other way round.

Just so you know, maximum current is drawn at start-up, when all the internal motors (fans, drives, etc) need to overcome the inertia of not moving, which means that your 430W PSU is far less likely to fail on start-up than your 400W was.

[patchoo78]

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@cq_tech wrote:
Yes Patch, it's perfectly safe, and will probably even run slightly cooler than your previous 400W PSU. A general rule of thumb is that it's perfectly OK to change to a higher-rated power supply, but definitely not the other way round.

Just so you know, maximum current is drawn at start-up, when all the internal motors (fans, drives, etc) need to overcome the inertia of not moving, which means that your 430W PSU is far less likely to fail on start-up than your 400W was.

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Thanks CQ  I thought it would be ok but I always get Voltage and Watts mixed up.. I think the fact that I had two hard drives plugged in with only a 400W power supply is what might have blown up the first one.. Lucky my house is a computer graveyard.. 

EDIT: I have just discovered a 500W power supply.. Is that too much of a leap to install?

[patchoo78]

Now I have another question... The 500 Wat power supply I have found says on the label that it is 230V but under the power socket there is a sticker that says AC/220V..

The power supply came out of another PC I had so obviously it worked in that computer but I was wondering why there was a variation in Voltages on the power supply

[patchoo78]

Scratch that.. Neither the 430 Watt nor the 500W power supply would fit 😞 

[cq_tech]

As long as the 500W PSU physically fits, then you'd have more than enough available current to run plenty of accessories or extra drives if you wanted, and would certainly be understressed in your present machine.

Very few power supplies say 240V on their specifications, with the absolute vast majority stating either 220V or 230V. The point is, it doesn't really matter. Being switched mode power supplies, they can tolerate quite a variation in input voltage so as long as your 500W supply is well ventilated and free of dust (a problem with older machines), then go right ahead and use it if you wish. 🙂

[patchoo78]

Wll turns out that I can use the 500W.. When I said it didn't fit I thought it didn't have the extra 4 pin plug needed, it was there but I just didn't see it at first so now it's in and it works... Now for some more RAM!

[cq_tech]

I didn't see your previous reply, probably because you posted it at exactly the same time as I posted mine, but I'm pleased to hear that both PSUs fit, and especially that the 500W supply is working as expected.

Also, I suppose you already know that increasing the amount of RAM in your PC is the simplest & fastest method of increasing its performance and speed?

Unfortunately, my motherboard uses DDR RAM in which the largest capacity is 1Gb, so with only 2 slots, the most I can fit (and have done) is 2Gb, but even that made a huge difference to my machine's performance compared with its previous 1Gb (2 x 512Mb sticks).

[patchoo78]

Yeah the RAM in this one is DDR1 Also with only two slots.. I managed to find a cheap 512K  stick on here so with the other 512 stick in there it will take it up to  1 gig, which is not great but not bad for a PC I got for free... 

A s a bonus, I dug out some old graphics cards and they still work, so now I don't have to put up with onboard graphics at least 

[cq_tech]

Well that should release some of the system RAM that was being used for the on-board video, so you're already in front before you even upgrade your RAM.

However, with only 512Mb of RAM, a lot of time is wasted by swapping data to virtual memory (the pagefile on your hard drive) so simply upping that to 1Gb should have made a very noticeable difference.

I'm very happy with 2Gb here, but then I'm a bit of a dinosaur in that I'm still using Windows XP/SP3 which doesn't have the memory requirements of later Windows versions.