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I am not going to give the advice sought, but rather my opinon and that of others. Dont OC, the computer manufacturer has given you the most efficient computer, based upon its limitations. I have helped so many who have experienced BSODs and other problems due to OC.
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You can install the new ram, but if you have a virus there will still be problem. The virus however does not affect the ram. Once you get rid of the virus, you will be ok. That being, said, I would wait. Lets not try to create more issues before the prior ones are taken care of.

For the record, overclovcking is always worth it... Free performance and when setup its stable and 0 BSOD. So i fully disagree with rich.

If youre bsoding you are not overclocked properly. I run 4.0Ghz on my i7 950 24/7 365 and i fold@home, so i'm not just and idle computer.

All that said, you can't overclock. All but a scant few prebuilt computers have locked BIOS so its impossible. Then theres allk the cooling issues associated with prebuilts.

So yes your computer would rock overclocked, but its not possible, and would burn up yoyr parts if you do.

Btw, if Towns correct, and you have 16Gigs, and youre bsoding... its because of too much ram and not enough power.

I disaagree with Patomb, leave the computer at factory specs. The manufacturers of the computers know the best comb of speed and reliable performance. What you get with OC is not worth it (that last portion is subjective)

No the factories do not, they build their systems so that to get a more powerful setup, you have to buy a new one from them., Infact most prebuilts run more Vcore than is required. Most likely so thgat there is not a chance a power issue happens.

If that were true, then the chips would not have variables built into the cpu to change the speed.
The difference between the 1366 i5/7 chips is the multipliers... a 920 has a 20 multi, the 950 has a 24. Same exact chip.

Intel has designed their products to do it, and the companies purposely lock them out so as they can't. You can get the exact mobo oem in a hp or buy one from the manufactuer and it'll be unlocked.

All that said, overclocking isn't something that is easy or garrenteed to do, or to get a solid high oc... but it is definately doable, and has extended the life of many systems when they get older.

I replyed in your bsod topic on the psu, as its a completely different subject.