Here is motherboard
1 service mode jumper (Service_Mode)
2 RTC reset jumper (RTCRST)
3 battery socket (BATTERY)
4 PCI card connectors ( SLOT 2 & 3)
5 PCI Express x16 card connector(SLOT1)
6 PCI Express x16 (wired as x4) connector (Slot 4)
7 internal serial card connector (Serial2)
8 speaker connector (INT_SPKR)
9 PCI Express x1 wireless card connector (PCIE_WLS1)
10 thermal sensor connector THRM3)
11 fan connector (FAN_CPU)
12 power connector (12V POWER)
13 memory module connectors (DIMM_1-4)
14 front panel connector (FRONTPANEL)
15 Internal buzzer (BEEP)
16 password jumper (PSWD)
17 SATA drive connectors (SATA0-3)
18 intruder connector (INTRUDER)
19 internal USB connector (INT_USB)
20 front I/O connector(FIO)
21 power connector (MICRO_PWR)
21 is the Micro MOBO connector.
Found another picture, still hard to believe.
how about the SLOT u think it's will work fine the 7750 ??