I'm inclined to agree with o1die. Which utility/software did you use to obtain those readings?
Here is a direct quote from the SpeedFan FAQ page:
"Hardware sensor chips are generic devices that can be used to measure voltages from anywhere. The measured voltage must be converted to the range required by the sensor chip. Standard monitoring chips specify which external circuitry must be used in order to measure voltages outside some range. Voltages like 12V, -5V, -12V and some others need this external circuitry. Some manufacturers chose not to follow datasheets. If this is your case, then you will read unusual values from SpeedFan. Since this custom circuitry is not known, SpeedFan does not try to "guess" it as any reading wouldn't be safe. If you get really odd voltage readings, simply enter configuration and uncheck the relevant ones."
It's been commented here many times that third-party voltage monitors often are wrong because they don;t have intimate knowledge of the way the mobo sensors were "calibrated" (or miscalibrated as Speedfan might contend). But if your BIOS Setup screens have system monitor displays you probably can see voltages there, and likely fan speeds and component temperature, too. Those are MUCH more likely to be correct, so look for them.
My own mobo from ASUS has such items in the BIOS. More to the point, the CD that came with it had many utilities, among them a Windows app that puts selected monitored items on the screen so you can watch them during normal operations. Do you have any such utility supplied by the mobo maker?