Hello First I want to say that my native language is not English . If I have made any grammatical errors ask to be excused . Recently I decided to improve my computer 's video card and bought a GTX 660 DirectCU. Once I put it in my computer , he began to beep and the card does not start at all. I went to the computer service and asked what could be my problem . There I was told that most likely my power is insufficient. So before I invest in new power want to ask - is it possible that the problem lies elsewhere. In the end it was pretty old computer and there may be some incompatibility ... On the net I found this Spoiler: My pc: Power Supply 475 watts wide-ranging, active Power Factor Correction, 85% Efficient Computer: Computer Type ACPI x64-based PC Operating System Microsoft Windows 7 Home Premium OS Service Pack Service Pack 1 Internet Explorer 11.0.9600.17691 DirectX DirectX 11.1 Date / Time 2015-03-30 / 09:01 Motherboard: CPU Type DualCore Intel Core 2 Duo E8600, 3333 MHz (10 x 333) Motherboard Name Hewlett-Packard HP xw4600 Workstation Motherboard Chipset Intel Beachwood X38 System Memory 4080 MB (DDR2-800 ECC DDR2 SDRAM) DIMM1: Micron 18HTF25672AY-800E1 2 GB DDR2-800 ECC DDR2 SDRAM (6-6-6-18 @ 400 MHz) (5-5-5-15 @ 333 MHz) (4-4-4-12 @ 266 MHz) DIMM3: Micron 18HTF25672AY-800E1 2 GB DDR2-800 ECC DDR2 SDRAM (6-6-6-18 @ 400 MHz) (5-5-5-15 @ 333 MHz) (4-4-4-12 @ 266 MHz) BIOS Type Compaq (08/28/08) Display: Video Adapter NVIDIA Quadro FX 3700 (512 MB) Storage: Disk Drive ST3640323AS (640 GB, 7200 RPM, SATA-II) Disk Drive WDC WD10EZEX-00BN5A0 (1000 GB, 7200 RPM, SATA-III) Optical Drive TSSTcorp CDDVDW TS-H653Q [ BIOS ] BIOS Properties: Vendor Hewlett-Packard Version 786F3 v01.15 Release Date 08/28/2008 Size 4 MB System BIOS Version 1.15 Boot Devices Floppy Disk, Hard Disk, CD-ROM, ATAPI ZIP, LS-120 Capabilities Flash BIOS, Shadow BIOS, Selectable Boot, Network Service Boot, EDD, BBS Supported Standards DMI, ACPI, PnP Expansion Capabilities PCI, USB Virtual Machine No From my research so far my power supply should be enough for this video card.