Tested three different IDE versions under an XP VM environment.
1.0.6
1.56.5-r2
1.6.9
with an identical to yours CH340G board and a ProMini with the Uno bootloader installed. This was loaded by selecting the Uno board tye and then burn booloader in the IDE. Connections are:
CH340G ProMini
DTR <----> DTR
RXD <----> TXD
TXD <----> RXD
VCC <----> VCC
CTS
GND <----> GND
All three versions yield the same results:
Board type: Uno - Uploads and runs
Board type: Duemilanove w/328P - Uploads and runs
Board type: ProMini 5V w/328P - Uploads and runs
Based on the above, I would suspect that either you don't have a Uno bootloader installed or the fuses are set incorrectly on the target device.