What is the exact model # ? Your missing a number, as the "p" should have 4 numbers then a letter or letters.
The HP 595 series utilize an HP proprietary designed power supply. It is NOT an ATX off the shelf power unit. Here is a spreadsheet of examples, cross referenced to PSU and GPU. Examples of the HP 595 series are shown.
Keep the card at 9.3" long or less. That way it will drop in without hassle. Picking a card requires matching it to a PSU. All cards are not the same, every manufacturer can change length and power requirements. Some 75W cards have need for a PCIe 6 pin power plug.
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HP Envy 8 5010 Tablet (2) HP DV7t i7 3160QM 2.3Ghz 8GB Printer -- HP OfficeJet Pro 8620 Legal Custom Asus Z97D, I7-4790k, 16GB RAM, WIN10 Pro 64bit, ZOTAC GTX1080 AMP Extreme 3 fan 8GB RAM, 500GB SSD, Asus PB287 4k monitor, Rosewill Blackhawk case and 750W OCZ PSU.
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