Watercooling temps

I got my watercooling kit on tuesday. I don't have a radiator yet, as I get my reservoir/radiator thingy in July. For now, I'm running it using a 25 liter reservoir...
I was wondering about the temps. The maximum temperature is 40C with Hmonitor, 38C with MBM. That doesn't matter now.
What I'd like to know, is how much will a "normal" radiator drop the temperatures.
The tbird is now pushing about 70W of heat @1102(8x138MHz)/1.91v.
If any of you would be so kind as to drop your clocks to that and check the stabilized temperatures, I'd be grateful.

Thank you in advance.

Look at my sig, I just run the DD cube and DD kit to get those temps at 1.85vcore and 1470mhz. So that should tell you that you should receive a GREAT deal of decrease in temps with a radiator when working properly.

Thanks!

I'll be expecting atleast 5C drop, realistically, I think.

i suppose it would really depend on the dimensions and efficiency of the radiator and how much air you suck through it. it is possible to get within a few degrees of ambient