The problem you have mentioned in your questions is very rare Mr. Xyjimenez. It’s something which really I heard fist time. You please just take the following steps that may secure your Vostro 3450 laptop.
1. Did you add any new hardware with your Vostro 3450 laptop recently, remove that.
2. Did you install any new software in to your Vostro 3450 laptop, uninstall it.
3. You must have installed any Antivirus too on you system uninstalls it but if you have installed Microsoft Security Essential then its ok.
4. Now try to scan your system and check viruses and malwares and remove them.
5. Update your all software’s like, VGA, SOUND, BIOS, and windows too.
This is not the problem of battery or its charging, because you said that the problem is with your monitor screen.
If you have a problem in clock settings the we can proceed a matter to resolve it, keeping in view if you have any other anomaly in accordance with this concern then you have to write it otherwise you should go to the technical support of Dell company.
Against your second question, according to my understanding the basic problem is related to your RAM [Random Access Memory] not about VGA memory.
The RAM memory varies according to memory size as well as different types in connection with 32-bit or 64-bit, also RAM is dependent upon the system design and its architecture.
In the Windows you can only view a portion of your physical 8GB of RAM, having ‘Memory Mapped IO [input output] Reservations’.
They overlap the physical address space and mask these physical addresses so that they become reserve and cannot be more useful for any other purpose.
If you go into your BIOS [Basic Input Output System] Interface you can see the total memory of your RAM.
I’m not sure if all Dell Vostro 3450 laptops have the same specs but here’s one I found. The Dell Vostro 3450 laptop ships with Intel Core i7-2620M Dual-Core 2.7 GHz, i5-2410M Dual-Core 2.30 GHz, or i3-2310M Dual-Core 2.10 GHz processor; integrated Intel HD 3000 with 1.6 GB video RAM or AMD Radeon HD6630M with 1 GB video RAM; up to 6 GB DDR3 SDRAM (2 slots); 500 GB SATA hard drive; and 8x rewritable DVD drive.
For networking, it includes an integrated Gigabit Ethernet card, Intel WiMAX/Wi-Fi 6150 mini card 802.16e (1×2) and 802.11 b/g/n (1×2), Dell Wireless HSPA 2.0 or EVDO-HSPA mini-card for WWAN, and 802.11a/b/g/n and Bluetooth Combo (BT V3.0 + HS).
For interface, it has one (1) RJ45 network connector, two (2) USB 3.0 ports, one (1) USB 2.0 port, one (1) USB 2.0/eSATA combo port, one (1) microphone jack, one (1) headphone/speaker out, one (1) HDMI connector, and one (1) 15-pin VGA video connector. For card reader, it has an 8-in-1 card reader. It ships with either genuine 64-bit Windows 7 Home Premium or Professional.
To get the exact video RAM of your video card, you can open the Microsoft DirectX Diagnostic Tool. Press the Windows key + R to bring up the “Run” dialog then type the following command and then hit Enter:
Go to “Display” tab and from there, you can check the “Approx. Total Memory.”