The Wiki is usually kept up to date, so it is a good place to look.
The original capacitors used in Toppy PSUs are not the best quality, but there is no evidence that they were ever 'dodgy' in any way. They are similar to the ones used in Humax PVRs, but because Humax fit a fan, their capacitors last much longer.
Fitting a fan is recommended for all Toppies, but particularly for 5810s. It doesn't need to run fast, so it can be very quiet. There are various threads about doing this in the Firmwares, enhancements and upgrades section.
If your Toppy is a number of years old, some its capacitors will probably be out of specification. It's not a matter of if they will fail, it's just when. A 5800 will be OK for up to 5 years provided it has good ventilation and is put into standby when not in use. A 5810 will not last so long and I've seen failures at 2 years; this is mainly due to fewer ventilation slots on the 5810. Higher temperatures lead to earlier PSU capacitor and HDD failure.
Early 5800 PSUs used brown Sam Young capacitors. If your Toppy's PSU still has these, they should be replaced as soon as possible.
On later models, different capacitor types were used. Although the black Samxon capacitors were slightly better, the green Samxon capacitors were, if anything, worse. These often dome when failing, unlike the brown or black ones which show no physical signs.
Replacement capacitors should be low ESR (impedance) 105°C types from a reputable manufacturer. These should last significantly longer that the originals. The current recommendation is to replace all 18 capacitors in a 5800 PSU and 13 in a 5810 PSU. Kits for DIY repair are available from me (and MikeyP) at very reasonable prices, and are much better quality than the capacitors available from Maplin. If you prefer, both MikeyP and I offer a repair service too.
If you suspect that your PSU may be failing, and you have access to a meter, measuring the voltages on the PSU edge connector is the best way to confirm it. Be VERY careful when doing this, as the large heatsink is at about 400V and will give you a nasty shock if touched. The key voltage is 5V, as the PSU uses this for regulation. If the 5V goes slightly low (4.9V or less) other voltages rise significantly and can eventually cause damage to some mainboard components and/or HDD.
Here are nominal and typical values for a 5800 PSU (HDD running):
Code: Select all
Marked Measured 30V 30V - 31V 22V 24V - 25V (wrongly marked on PCB) 17V 16.5 - 17.1V 8V 7.4V - 7.6V 5V 5V 3.3V 3.3V (has its own regulator) 15V 15V - 15.6V 12V 12V - 12.8V
There is further information on my website including a list of known faults for 5800s and 5810s.
YouTube time-lapse PSU repair (5800 type)