my new computer just got here and i am downloading a fresh copy of the game and once i have it running i will report here in this thread or it performs at various resolutions.
i also have the option of plugging in a 1920x1200 monitor and turnig off the builtin 5k if needed here are the specs of the new computer
Model: iMac15,1, BootROM IM151.0207.B00, 4 processors, Intel Core i7, 4 GHz, 16 GB, SMC 2.23f11
Graphics: AMD Radeon R9 M295X, AMD Radeon R9 M295X, PCIe, 4096 MB
Memory Module: BANK 0/DIMM0, 8 GB, DDR3, 1600 MHz, 0x80AD, 0x484D54343147533641465238412D50422020
Memory Module: BANK 1/DIMM0, 8 GB, DDR3, 1600 MHz, 0x80AD, 0x484D54343147533641465238412D50422020
AirPort: spairport_wireless_card_type_airport_extreme (0x14E4, 0x142), Broadcom BCM43xx 1.0 (7.15.124.12.8)
Bluetooth: Version 4.3.0f10 14890, 3 services, 27 devices, 1 incoming serial ports
Network Service: Ethernet, Ethernet, en0
Network Service: Wi-Fi, AirPort, en1
PCI Card: pci11c1,5901, IEEE 1394 Open HCI, Thunderbolt@195,0,0
Serial ATA Device: APPLE SSD SD0128F, 121.33 GB
Serial ATA Device: APPLE HDD ST3000DM001, 3 TB
USB Device: BRCM20702 Hub
USB Device: Bluetooth USB Host Controller
USB Device: FaceTime HD Camera (Built-in)
USB Device: Razer Naga
USB Device: DT 101 G2
USB Device: USB 2.0 Hub
FireWire Device: d2 quadra (button), LaCie, Up to 800 Mb/sec
Thunderbolt Bus: iMac, Apple Inc., 26.1
Thunderbolt Device: Thunderbolt to FireWire Adapter, Apple Inc., 1, 5.6