Hi Vraciu,
By chance do you know what the specs are on the 2Gb x 2 DDR3 mem kit you're running? Especially CL and Freq?
I ask this as I had looked at the specs of your computer and noted that your mobo can accept some pretty high freq mem (PC8500).......
You could squeeze a little more performance out of your current rig by swapping in a faster set of mem modules over the existing mem modules you have by reducing the amount of time it is taking for the mem to transfer data when called for and to move more data within the same amount of time across the rising and falling mem clock cycles. Now what I'm about to suggest doesn't take into account the mem clock "wait" or "hold" time (the time in nano secs for the mem clock to switch\reset from the end of a rising clock cycle to the start of a falling clock cycle and vice-versa) or mem power stability which can vary depending on several variables but in the scheme of things will usually impart a very small\minor impact to the overall performance of a mem module outside of the cas latency\frequency relationship during the rising\falling clock cycles so the CL\Freq is the main relationship to focus on......to determine mem PERFORMANCE.
To determine the faster mem module just divide the frequency number by the cas latency number to get a final number of what the mem module in question could actually move within this total rise\fall clock time interval.....the larger the result, the faster the mem module but for the result to be noticeable the difference threshold needs to be at least 20 between the 2 to effectively account for any unforeseen variables. This is a simple formula to use to determine this by. If you want, you can search for sites that provide calculators to do the same thing that take in more of the variables to get a more accurate result but what you'll find is that the results of this simple formula will be very consistent to them..........
Example 1(I'm using some DDR4 mem I have as I know the CL & Freq numbers of it):
1. DDR4 13cl x 2133freq vs DDR4 15cl x 3000freq
2133\13 = 164.08 vs 3000\15 = 200.00 w\ spread of 35.92 so the DDR4 15cl x 3000 mem module is the faster mem module that the mem performance difference will most likely be noticeable between the 2 (you'll see and "feel" the difference when using your box).
Example 2:
2. DDR4 13cl x 2133freq vs DDR4 14cl x 2400freq
2133\13 = 164.08 vs 2400\14 = 171.43 w\ spread of 7.35 so the DDR4 14cl x 2400 mem module is TECHNICALLY the faster mem module, but the performance difference is so slight that you most likely won't notice it\notice a worst result due to the other variables not being effectively accounted for cancelling the small gains out. Now if you could find the same 2400 freq mem w\ a lower cl number the game can change (or the same 13 cl mem w\ a higher freq number)......
2133\13 = 164.08 vs 2400\13 = 184.62 w\ spread of 20.54......now you will most likely be able to notice a small difference in the performance as the spread between the 2 is large enough to actually make up for\overcome other variables not accounted for w\ some extra performance to show up visually and in "feel". The larger the spread is, the more noticeable the result will be until you meet\exceed the capacities of the rest of the system bus traces on the mobo (which usually should be the bus between the CPU and mem\DMA controller(s)). Any mem module performance gains past this point is wasted\useless.
The idea is to find the fastest overall mem modules (lowest CL w\ highest Freq) to use for the lowest\most practical costs that can meet\exceed expectations and work on your mobo w\o having to downclock it to fully optimize your existing computer's performance to the best you can within the limitations you're facing, and just using either the CL number or the Freq number alone can\will be somewhat misleading.....unless you actually hit the "numbers" by chance......
Of course the other option is to overclock the existing mem module's frequency to achieve the same result but now the power stability issue comes into play, but it's free performance if achievable......
Just putting this out there for your consideration if getting all the performance out of your existing box is what you're really wanting to do at this time. Now if you've already done this then good for you!
I now do this myself up front when I either upgrade to a new mobo or build from scratch w\ a new mobo as this also can save money over time.
Hope this can help you out.