As noted by Creative Labs that series of sound cards has been classified as "End of Service Life" way back in 2005. So it is no surprise there are no Windows 7 or later drivers for it. Therefore, you are stuck with the on-board sound, or you need to upgrade your sound hardware to something more modern to match the more modern OS.
That said, I am surprised you feel the on-board sound is "terrible". There have been HUGE improvements in on-board sound in recent years as more and more users are demanding it and often using their systems in home theater setups where high quality audio is a must. So the motherboard makers, especially the major ones like Gigabyte and ASUS are including better sound devices on their boards.
Note H61 is used on a whole series of Gigabyte motherboards so we need the full model number to really know what we are talking about. But I note this Gigabyte H61 board includes the Realtek ALC889 audio chipset and that has some pretty impressive specs and reviews.
That is not to say the on-board is audiophile quality - it isn't. But then neither are ANY self-powered computer speakers either. If your speakers are as old as your SB, you may consider a new set of speakers.