I don't know: the max combined wattage isn't specified on those psu's, so you either have to e-mail the manufacturer for that or just get something else, like a Corsair/Antec/OCZ.
It also depends on your other components, how many hard drive's do you have, what kind of CPU, etc... If you have 1 hard drive and a typical 65W (core 2 duo or athlon X2) or 95W (core 2 quad) CPU you need 22A or 23A on the 12V rails, if you have something bigger like a 125W (Phenom X4) or 130W (core i7) CPU you need even more power.
Your best bet would be an OCZ Stealthstream 400W, or a Corsair CX400W, those can power your 9800GT + an overclocked quadcore and 1 or 2 hard drives.