I would not buy an 8 yr old window 7 laptop. Laptops do not normally get "refurbished." Laptops do not usually last for 8 yrs. You will not be able to get a genuine Dell replacement battery. Windows 7 is unsupported after Jan 14, 2020. Buy a newer or new laptop.

The video was not upgraded after purchase so it still has the original board. You cannot upgrade the gpu. That card was ordered at the time of purchase and the CPU might have been ordered then too. See the standard specs in this review From a review--

 Users can order NVIDIA NVS 4200M  (at the time of purchase)

@Mary G 

Just because you would not buy an 8 year old laptop does not mean that others should not.

It may have been sold with W7 installed but that does mean that it cannot be upgraded to W10.

I am like many others a Microsoft Registered Refurbisher.

We all Refurbish laptops and I have done so for over 12 years.

I sell refurbished E6420 XFR's with W10 installed every week.

As far as batteries.

NEW Dell OEM Original Latitude E6420 6-cell Laptop Battery 65Wh - N3X1D

https://www.parts-people.com/index.php?action=item&id=14905

The OP does not say if they are using W7 or not.

I have dozens of systems that have W7 installed and will continue to use them for years to come.

Buying a newer laptop is not always the best or only solution.

Best regards,

U2

Windows 7 will work after January obviously, but you have to consider how long will browsers support it, or third party software. As for GPU your upgrades will have to be a similar vintage which will be used parts about as old and not give you really any performance gains. Most likely the current hardware cannot even run Windows 10 since no drivers are provided for the hardware. It might work sort of, but given the age of hardware it may not support some new technologies anyway. Before investing any money in such a old laptop I would seriously put that money to better use buying a new or newer laptop. I have a 5 year old Latitude that has already lost support for any driver updates and your older laptop probably hasn't received any driver updates in years. Laptop's as far as hardware are basically frozen in time, unlike desktop PC's where you can upgrade a GPU or CPU even upgrade a motherboard to work with newer CPU's your laptop has none of this flexibility.   

@Johnnythegeek 

The OP has not posted what version OS is installed.

But to state:

"Most likely the current hardware cannot even run Windows 10 since no drivers are provided for the hardware."

Is incorrect:

Most of the drivers for the E6420 XFR are the same for the E6420. "Except BIOS Updates"

My company sells Refurbished Dell E6420 XFR's with W10 installed just about everyday.

We also donate Refurbished Dell E6420's 2-3 times a year with W10 installed.

With W7, W8, W8.1 and W10 it is not the IE browser support that will be questionable it is weather Websites will support the IE 11 browser.

IE 11 will get Technical Updates as long as Windows 10 gets supported.

Best regards,

U2

I was just referring to Dell’s own Windows 10 compatibility chart https://www.dell.com/support/article/us/en/04/sln297954/dell-computers-tested-for-windows-10-may-2019-update-and-previous-versions-of-windows-10?lang=en#One

which none of those models are being supported or tested to work with current Win 10 released. As I mentioned it may or may not work with generic or even older drivers but Dell will not fix or release new ones. Would I trust Windows 10 to continue to support such old hardware? No 

a new motherboard costs how much?

A brand new laptop with 64 GB eMMC hard drive is about $150 on sale.

That's my benchmark of whether I should spend more $ on an 8-year old laptop or not.

$25 or less ... yes

$25 - $50 ... maybe

$50 or more ... no

.

You really don't know you're . M G you can install windows 10 on laptops tht old ffs u can even install them to 19 yr old laptops and laptops do get refurbished you conk. Get with the facts you uneducated boomer