In classic sleep mode, a PC stores it's RAM data to it's hard disk and then shuts HDD down. So, there is no way at all to run something that way. But, some mainboards (e.g. some of ASUS's ones) do support their own, let's call it "light" sleep mode. During "light" sleep it is possible to run some processes (however, CPU is usually downclocked, so you can lack it's performance for running a bot). If you care, you can post here your motherboard model and I'll tell you if it's possible to enable that "light" sleep mode on your PC.