Tadpole/RDI UltraBook NVRAM problem...

Dear Vintage-Computer experts, over the last year I "lost" two Tadpole/RDI UltraBook notebooks. These are Ultra Sparc based machines available in various configurations. Both machines refuse to boot, i.e. they pass all tests and print the right messages, but after initializing the memory they fail to load the kernel (boot disk) or do not send any network messages (boot net). I noticed, that there appear strange strings in the environment variables for hardware-revision for example and further investigation shows that the NVRAM (DS1643) must have lost a part of its content which are filled with e.g. 55 hexadecimal now. My question is, whether someone out there has got such an UltraBook up and running and is willing to read out the NVRAM and send me the contents. The machine has not to be opened to do this since the contents can be listed via the OpenBoot firmware. As most of the bytes should contain 00 it would for example be sufficient to take some low resolution photographs of the hex dump pages containing non-zero bytes and I'd be happy to type them into a hex editor myself... I'd post step by step instructions how the NVRAM's contents can be displayed... Best regards, Erik. P.S. The two UltraBooks are of the following type: U20-14-9-512P, Part No MU20014PCI36, Serial U20/1040, Serial ID 8527455. This one has got THREE hard drives. U200-14-3-128P, Part No MU20014PCI36, Serial U20-1253, Serial ID8526256 with two hard drive bays and one for the battery.