I have a USB powered midi keyboard (M-Audio KeyRig49). The USB cable it came with is quite short, and barely reaches the front USB 2.0 port. I also have front USB 3.0 ports. Ideally I would have liked to plug it into one of the rear ports. Would plugging it into the front USB 2.0 port affect performance compared to rear 3.0 ports? I have heard that the power of the front ports are not as great as those on the rear. Also, would I be able to get a longer USB cable and plug it into a rear port? Or, would that not supply enough power to the device?
The USB cable adapter is USB 2.0. On the keyboard box, it states as minimum system requirements 'one native USB port'.
If it was made for USB2 plugging it into 3 should not make any difference on terms of quality or speed.
You are right about front ports sometimes being weaker power wise, only one way to find out is to try it. If it works great but if not back will be the only option. Usually this only effects things with a higher power draw though like portable spinning rust HDDs, lower power stuff like a keyboard should be okay. EDIT 2: the front ports are connected to the motherboard on some cheap cases with unshielded twisted cables, these will generally be the ones not capable of the power out put or signar interference. The ones connected to the mother board with proper thick shielded cables to the front ports are usually fine. For reference I have a H440 NZXT case and it is all quality parts with no issues.
For the longer cable, is the one on the keyboard replaceable or hard wired? If replaceable a good quality cable can make a difference with stable power over length. Again with my portable HDD some long cables did fine. But some lower quality ones could not power it.
Edit: for reference I have an Ableton Push controller and it runs fine over front USB2 port port with a long (2m~) cable but a nice one not a cheap thin one.
Edit the third: Sorry I just woke up so information is coming in bursts. If the front is not able to supply the power and you cannot make it to the back ports a powered USB hub to the front and the keyboard into the powered hub will work as all the front ports has to do then is pass information the hub will do the power part.