Here is a good question

[Gunnykat{MEOW}]

Hello guys its me again always some thing. The Rig is great now my Internet connection speed thats normally 27.50mbps drops down to 4.85mbps. If i reset my modem and router it goes back to normal and then drops again later. Any Ideas. I am using a Motorola SB5101 Surfboard Cable Modem A linksys WRT160N V3 Router. My computer OS is windows 7 Home Premium.

[THEKATZ*{MEOW}*]

Have you tried this with out the router and do a good test of it?  It would be nice to eliminate the router as this can be as simple as a cable modem issue.   You should do this without the router and test your speed several times through out the day.
Of course if you get the same results and the issue points to the modem, then it is time to call your ISP (Internet service provider) and have them assist you with no mention to them of the router - Trust me, if you know the router is not the issue then DO NOT include this with your comments to your ISP, otherwise a whole new can of worms are opened.  Have them fix your modem or replace it.  
Test the new modem to make sure you have the speeds you expect and then reconnect your router.

If this is a router issue, get back with me on that.

TK

[Gunnykat{MEOW}]

I beleave its the routor. Earlier i was unpluging both. So I decided to wait till it did it again. so when it did i unpluged the modem first. No Change after restart. So then I did the routor bingo it reset and all was at good speeds. So is there a seting that I might need to do.

[THEKATZ*{MEOW}*]

Well, lets start here. I personally would not be satisfied I have eliminated the SB Modem unless you have actaully tested this without the router.
On the other hand it sounds like you have a good handle on what you have here.

Question - do these speed affect any wireless connection (Have you ran a speed test from a wireless laptop to see what it's speeds record?)

Usually the fatory settings (minus any security settings) should produce top speeds.  When you describe that after a bit it slows, something makes me wonder if QoS has been modified?
I have not dealt with some of these types of settings but as I understand, you can 'throttle' certain connections to allow better performance for other connections. (More than likely deisgned for commercial use in small business to even out or rout more important bandwidth)
Though I beleive that QoS at factory setting should not be an issue.

Sorry, there is just not a lot of issues on that modle of router out there to find.  Keep me posted

[Gunnykat{MEOW}]

Found a post on their website stating that some new computers fill up the cache quicker. So I updated the routers firmware and wola its fixed who would have thought. Now I get and my ping is . Thanks TK for giving me the Idea to check the modem direct.  That saved the day.

[THEKATZ*{MEOW}*]

Your very welcome - glad you have it running at good speed.

[Gunnykat{MEOW}]

Me too bud. It's cause of you guys I have the most awesome Rig. Thanks for all the Intell. I have learnt so much from all you great teachers.