Hello,
I have this generic "The Best Power" MT-500P 500W ATX power supply since 2005, and it's been laying around for a little while since I have no PC to put it in currently. I was bored and decided to "rebuild" it to improve it.
Here's what it looked inside at first:
The electrolytic capacitors on the secondary side of the power supply looked small, and the input transient filter was missing all its components (X cap, two Y caps, and one coil) which wasn't good. Most likely those parts were not used in this power supply to cut cost.
A while ago I installed a red LED fan I had:
For improving the power supply, I replaced all of the electrolytic capacitors on the secondary side with larger high-quality Japanese low ESR capacitors (Nichicon, United Chemi-con, and Panasonic capacitors). Also, all of the tiny electrolytic capacitors around the PCB of the power supply were replaced also.
I also added in the components (yellow X cap, two blue Y caps, and one coil) to the input transient filter, the components were collected from older power supplies no longer in use.
In the end, this is what the power supply looks like inside after my modifications:
It works perfectly powering an old Celeron 2.2GHz computer system, and the voltages were:
+12V = 12.13V
+5V = 5.17V
+3.3V = 3.43V
-5V = -5.10V
-12V = -11.53V
(the +12V, +5V, and +3.3V measurements were taken with a digital multimeter while the -5V and -12V readings were from the motherboard)
All voltages were within ATX specifications and were solid and stable.
The specifications of the Celeron 2.2GHz PC I had are:
Intel Celeron 2.2GHz processor (Socket 478)
1GB Kingston ValueRAM KVR400X64C3A/1G DDR400 PC3200 RAM (1x1GB)
VIA P4PA-UL motherboard
"Diablotek" ATI Radeon 9600XT 256MB DDR AGP 8X video card
40GB Maxtor PATA Hard Drive
L&C LC-B450 E 450W Power Supply (I have done modifications to make this power supply better also)
Microsoft Windows XP Professional SP3 x86
Old beige generic mid-tower ATX case