CPU Burn-in can achieve slightly higher temps than Prime95, but if all you want is higher temperature then just stop the fan on your heatsink. Prime95 is not just executing demanding code on the chip, it checks the results. So it's actually testing the chip (vs just stressing it).
But since you have an HT-enabled CPU, you can try to get the best of both worlds. Run 1 instance of Burn-in and 1 of Prime95. Open up task manager to make sure each program is using about 50% of the processor time, then leave it alone for 12-24 hours. You could also experiment with two instances of Prime or two of Burn-in, but it's usually best to have Prime in there for the error-checking.