Frequent Kernel Panics and freezes on 10.7.5

Hi,

I have a MacPro1,1 running

Processor 2 x 1.86 GHz Xeon E5320

Memory 14 GB 667 MHz DDR2 FB-DIMM

Graphics ATI Radeon HD 5770 1024 MB

Software Mac OS X Lion 10.7.5 (11G63)

It experiences frequent to Semi Frequent crashes. The crashes are either full-out kernel panics as listed below. However far more frequent are the "freezes" which simply leave the computer "locked" and unresponsive, but powered on. These stump me more than anything else as they cannot be overrident by hardware or software. At least with the kernel panics the machines reboots eventually.

-rw-rw----@ 1 root admin 6656 26 Dec 14:28 Kernel_2012-12-26-142834_ElitePro-2.panic

-rw-rw----@ 1 root admin 7421 29 Dec 21:11 Kernel_2012-12-26-144050_ElitePro-2.panic

-rw-rw----@ 1 root admin 8276 29 Dec 21:11 Kernel_2012-12-29-155613_ElitePro-2.panic

-rw-rw----@ 1 root admin 7676 8 Jan 01:37 Kernel_2013-01-01-210956_ElitePro-2.panic

-rw-rw----@ 1 root admin 7573 8 Jan 01:37 Kernel_2013-01-07-201034_ElitePro-2.panic

-rw-rw----@ 1 root admin 7262 15 Jan 05:17 Kernel_2013-01-10-200300_ElitePro-2.panic

-rw-rw----@ 1 root admin 8542 15 Jan 05:17 Kernel_2013-01-13-134451_ElitePro-2.panic

-rw-rw----@ 1 root admin 7482 22 Jan 06:08 Kernel_2013-01-16-084336_ElitePro-2.panic

-rw-rw----@ 1 root admin 7382 22 Jan 06:08 Kernel_2013-01-17-083933_ElitePro-2.panic

-rw-rw----@ 1 root admin 7513 22 Jan 06:08 Kernel_2013-01-20-150603_ElitePro-2.panic

-rw-rw----@ 1 root admin 6621 23 Jan 23:40 Kernel_2013-01-23-234042_ElitePro-2.panic

-rw-rw----@ 1 root admin 6194 24 Jan 08:08 Kernel_2013-01-24-080838_ElitePro-2.panic

So a few caveats up front:

1) the CPUs were upgraded to run a series of enterprise packages (Virtual Machines and more where we needed at least six spare cores). These were typed to the Mobo series and ran without issue for six months.

2) The Video card was upgraded to aa Apple-supplied ATI Radeon HD 5770 (so we coudl run triple displays)

3) the Main drive is an OCZ-VERTEX3 MI Media SSD.

Each have been swapped out at various times earlier in the last year to isolate the panics or to fins the defective parts. RAM was checked as well.

So I'm stumped. I can provide more machine information to post if needed.

Any ideas?