https://download.lenovo.com/ibmdl/pub/pc/pccbbs/mobiles_pdf/43y6630_03.pdf
Page 48 gives the memory configuration. Looks like 4 GB is as much as
you can install whether it be one 4GB module or two 2GB modules. That's
for "standard memory", whatever that means. There is a row in that
table for "optional memory" that shows another 4GB module can be
installed, so you could have 8GB in that laptop. Are there really 3
slots for memory, or just 2? If just 2, looks like you can put in two
4GB modules: one in the "standard" memory slot, and another in the
"optional memory" slot (I'm assuming the 1st slot is "standard" and 2nd
slot is "optional").
Page 70 shows where to install/change memory modules. If you use only
one 4GB module, it goes in Slot-0 (lower connector). If you use two 2GB
modules, one goes in slot-0 and the other in slot-1.
There is no mention of where to find the "optional" memory slot.
Probably have to remove an access panel on the bottom. However, you may
not have that feature.
An online copy of the manual is found at:
https://www.manualslib.com/manual/783635/Lenovo-Thinkpad-T500.html?page=58#manual
Page 58 is where memory change is described. "Optional memory" just
seems to refer to the standard memory module compartment where there at
2 slots where you can use 1 module (lower slot-0) or 2 modules. That
laptop apparently has a limit of 4GB addressing, so you can put one 4GB
module in slot-0, or two 2GB modules in both slots. Specifications in
that manual do not state the maximum memory capacity. That's why I
found the hardware servicing manual which indicates 4GB total.
http://www.notebookreview.com/notebookreview/lenovo-t500-thinkpad-review/
That mentions "... gain access to an open WWAN slot, another for Turbo
Memory or UWB, two DDR3 memory slots, ...". So, there are the two
SODIMM slots, but maybe there is a smaller card slot to add something
like an SD card. "Turbo Memory" is mentioned at:
https://support.lenovo.com/us/en/solutions/migr-71355
On that page, it mentions "Intel Turbo Memory Minicard". Found it
described at:
https://en.wikipedia.org/wiki/Intel_Turbo_Memory
Sure sounds like an SD flash memory card. Those will be a *lot* slower
than your main or system memory on the SODIMM modules. Found some pics
in an image search:
https://www.google.com/search?tbm=isch&q=intel%20turbo%20memory%20minicard
Nope, that isn't an SD card (other format flash memory card). That's a
special card you have to buy (but your description indicates you already
have one that adds 1GB).
https://www.newegg.com/p/0RN-0013-000F2?item=9SIAJCJ8HJ4470&nm_mc=knc-googleadwords&cm_mmc=knc-googleadwords-_-memory%20(desktop%20memory)-_-ibm-_-9SIAJCJ8HJ4470&source=region
$70 for a 4GB minicard. Sorry, I couldn't find specs from Lenovo saying
what is the maximum size that laptop will support.
You sure the minicard slot isn't already populated with a wifi card?
Seems to be the majority use for that slot.
https://www.crucial.com/compatible-upgrade-for/lenovo/thinkpad-t500-series
That indicates you could have 8GB in the laptop, but Lenovo's servicing
manual indicates 4GB is the max. You could buy their 8GB 2-module kit
to see if those work. Check Crucial's return policy before buying.
Since you hint you already have 4GB in the laptop, and assuming that is
with one SODIMM and not with two 2GB SODIMMS, you could buy just one 4GB
SODIMM. Because architecture can differ, I usually buy the memory
modules in sets where all are the same type from the same source.
I've found other memory vendors claiming the T500 can take 8GB (two 4GB
modules). If it takes 8GB, don't bother changing out the 1GB memory
minicard.
While you can add more system memory to reduce the chance of using the
pagefile which is on the slower drive (although you said you replaced
that with an SSD), you could also review what processes are running
memory, get rid of some, and free up some RAM. You may not really need
all those startup programs eating up memory.
The SSD will give you the most noticable speed boost for boot and
loading programs. You may not notice any boost going with more memory.