Thinkpad T530 Memory Slots

I have a T430s system and a W530 system .. each with a Samsung850 EVO mSATA drive. Using CrystalDiskMark, I'm getting sequential read/write speeds on the mSATA about half the speed of my Samsung SSD 840 Pro. All the sites I go to say they should be comparable in speed. Am I missing something? Is the interface that the mSATA plugs into down-level since it's PCIe 2.0? I didn't think the PCIe mattered - that it was a straight through to the SATA channel - or whatever. My ignorance on the hardware is showing, I'm sure ..

1. Lenovo W530 Memory Slots
2. Thinkpad T530 Specs
3. Lenovo Thinkpad T530 Manual

Buy Memory RAM Upgrades for your Lenovo ThinkPad T530 - 100% Compatibility Guaranteed. FREE delivery & Low Prices. 100% Safe & Secure. Memory Expansion Slots / Banks; 2 Sockets/4 Sockets: Memory Type & Info; PC3-0 DDR3 SODIMM 204-pin memory: System CPU Type; N/A: Memory Warranty; Lifetime Warranty. Guaranteed Compatible with IBM Lenovo ThinkPad T530 Laptop. Best choice memory for IBM Lenovo ThinkPad T530 Laptop Read MemoryStock Reviews. General Memory Installation Video. 'ThinkPad T530 and T530i have two memory slots, one under the keyboard and the other under the memory slot cover at the bottom side of the computer.' User Guide ThinkPad T530, T530i, and W530.

Any ideas? Is this normal? Will a later version system behave better?

Lenovo W530 Memory Slots

Thinkpad T530 Specs

Lenovo Thinkpad T530 Manual

Thanks ..