This threads a couple of weeks old now, but ...
The G'byte G41's work fairly well with the right CPU's. Using an E5200 series chip (200 MHz FSB), you will be limited by the CPU core speed. Using an E6500 or E7200 series chip (266 MHz FSB freq), you can achieve a moderate overclock while being limited by the G41 chipset 340 - 360 MHz upper FSB limit. Because there's so little headroom, CPU's with 333 MHz FSB freqs don't work well.
The newer G41's use DDR3 RAM, which is no real problem now because DDR3 is pretty cheap right now.
The best guide for G'byte Coer2 boards is this:
Shadow's Gigabyte motherboard OC guide:http://www.tomshardware.co.uk/forum/page-245679_11_0.html
It's for an EP35-DS3L but all the Gigabyte Core2 BIOS's are similar. The G41 will have fewer options.
Go through the guides. Then take your core voltage off Auto and set your memory voltage to factory recommended values. Change the System Memory Multiplier (DDR3 RAM) from AUTO to 4.0. Then when you increase the FSB, the memory clock will rise in in proportion with it. At an FSB of 200 MHz (E5200), your memory clock should be at 800 MHz.
I have an E6500 in a G41 (352 MHz FSB limit) running at 3.87 GHz which I think is "not bad for such a cheap system".