The only way to check this is by manually looking at your modules. However with a four slot machine like yours this is not an issue as you need to remove all of the existing ram to upgrade, but its worth knowing about.
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(8x4GB) PC2-5300F 667mhz. Will Fit Mac Pro 3,1 2008.
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Manufacturer: Hynix HYMP151F72CP4N3-Y5. Capacity: 4GB (1x4GB). HP ProLiant DL580 G5 series Dell PowerEdge 2950 Server Mac Pro 1.1 3.1 2006 -2008. HP ProLiant DL360 G5 series Dell PowerEdge 6800 6850 6900 6950 Apple.
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Mac Pro (Late 2019) (December 2019) Model ID: MacPro7,1 | 2.5GHz 28-Core. Mac Pro (Late 2019) (December 2019) Model ID: MacPro7,1 | 2.7GHz 24-Core. Mac Pro (Late 2019) (December 2019) Model ID: MacPro7,1 | 3.2GHz 16-Core.
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RAM Upgrade for Apple Mac Pro 2019 HYNIX 8GB (1X8GB) 1Rx8 PC4-2933Y.
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Compatible with all Apple Mac Pro 4.1 and 5.1 (2009 / 2012).
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16GB 8x2GB DDR2 667MHz PC2-5300 240-PIN ECC FBDIMM MAC PRO ORIGINAL/2006 RAM KIT (*****NEW*****)
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The product is a 8GB kit of Micron DDR3 RAM memory, consisting of 2 x 4GB modules with a bus speed of PC3-14900 (DDR3-1866). It has a total capacity of 8GB and features memory ECC. The RAM is designed for Mac Pro systems and has a factor form of DDR3 DIMM with 240 pins. Pulled from working Mac Pro A1486 units.
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