They both are fine. They both have the exact same specs and they both use TCCD chips.
What idiotec said...not only are they using different PCB, but as far as I know OCZ has also switched to TCC5's
Idiotec, yeah I've got that list at XS bookmarked, but it hasn't been updated in over a month. ...ehh scratch that just went and checked and said it was edited today lol....so hell I guess it is fairly up to date.
BTW, in regards to OCZ posting about TCC5s here it is on their site:
Following the lack of availability of TCCD chips, OCZ replaced TCCD chips with TCC5 chips on its Platinum DDR modules.
3.4v for BH-5's is just right on the verge to get them to shine...I'd say upwards of 3.6 to get them to their max potential...best I ever saw was the OCZ VX line at 3.7v and the dude doing 272Mhz at 2-2-2-2 timings lol