Voltage is a draw so it can be any amount higher than original. Sometimes higher voltage will be physically larger so watch out for that.

Ok that is what I thought so as long at the 16v's physically fit I'm good. thanks just need the sanity check

Scottmm wrote on 2024-04-26, 16:02:

When recapping a motherboard I know you have to match the capacitance for the caps but can go Higher on the voltage

You can also go lower in the voltage... but you really would have to know what you are doing / where you are doing that substitute.

For example, if a cap filters a 3.3V rail on the motherboard and a 10V cap is fitted in that spot, you can actually drop the voltage rating of the cap to 6.3V, if that is needed to make the cap fit. Likewise, on the CPU V_core, where voltages are often under 2V (at least for anything Pentium 3 and later) you can surely use 2.5V or 4V caps, even if the old caps were 6.3V or 10V -rated. But again, you just have to know what rails go where on the motherboard to make this kind of substitution.

As for using a higher voltage cap than what was originally there - no problem in doing that whatsoever... so long as you can get the replacement cap to fit. Higher voltage caps are typically larger. An added benefit of that, however, is that larger caps have (usually) larger ripple current handling rating... meaning, the cap can take more heating (both externally from the circuit and from its internal charging/discharing in the circuit), which means it will likely run cooler and probably last longer too.
So in general, physically bigger caps = them running cooler. Of course, large space isn't always a given.

Also, the brand and series of caps matters a lot too, as that dictates what impedance and ripple current specs the cap will have.
On that note, you can have a larger general purpose cap still have inferior specs to a smaller cap low impedance / high RC cap.
Moreso to the point, you should look up the datasheet for each brand and model (series) of the old caps to see if the new caps are even suitable in terms of matching or exceeding the impedance and RC specs. The new cap should have same or lower impedance (ESR) ratings and same or higher ripple current (RC) ratings.

Particularly regarding ESR (equivalent series resistor), some circuits rely on specific values (or close to them) and you have absolutely no idea what your specific circuit design does or requires if it was badly designed. So for this one, try to be as close as possible to the original.

Minutemanqvs wrote on 2024-04-29, 14:22:

Particularly regarding ESR (equivalent series resistor), some circuits rely on specific values (or close to them) and you have absolutely no idea what your specific circuit design does or requires if it was badly designed. So for this one, try to be as close as possible to the original.

Not really.
You can deviate quite a bit and still have a perfectly fine running motherboard.

Remember, most electrolytic caps are rated +/-20% on their capacitance spec... which is not a very tight tolerance.
The ESR/impedance can vary even more, depending on if the cap is at "standard" room temperature (i.e. 25C), closer to freezing temperature, or very hot from use. Not uncommon to see 10x difference in ESR between these... hence why datasheets of low ESR / low impedance caps also typically list a "cold" (freezing) temperature for the impedance. As such, circuits are often designed to handle this kind of variation in parameters.

So in short, you don't have to match the ESR very very exactly. Matching it to +/- 20 to 30% is good enough. And typically, going with lower ESR than the original can often be pushed even further (up to 50% lower.)